Since SUVs take longer to stop, should they have a lower speed limit?

[mbg]

...?

[FastFokker]

Wrong forum, but where is the data to show that SUV's take longer to stop?

What about trucks and vans?

[gei]

Please consult newton's laws of physics.

Heavier things take longer to stop.

[FastFokker]

Please consult newton's laws of physics.

Heavier things take longer to stop.Yes, if all other aspects are equal.. which they are not.

Transport trucks are allowed to do the speed limit, are they not?

[b0rk]

This is the dumbest thing I have ever heard of. Just because someone/something takes more do to something, you're going to penalize them? So if people smoke, are you going to charge them more for health care since they typically develop more health problems? Or, are you going to charge dumb university students more since they take up more of the prof's office hours?

[FastFokker]

In real life, vehicles stop the same.. (generalized)

The most important part is paying attention and response time of braking. If you're not paying attention and waste 0.5secs, you will stop farther.

[curtis]

Actually, you know.. that's not a bad idea. Maybe things SHOULD be that way. They just aren't... yet.

This is the dumbest thing I have ever heard of. Just because someone/something takes more do to something, you're going to penalize them? So if people smoke, are you going to charge them more for health care since they typically develop more health problems? Or, are you going to charge dumb university students more since they take up more of the prof's office hours?

[manho]

In real life, vehicles stop the same.. (generalized)

The most important part is paying attention and response time of braking. If you're not paying attention and waste 0.5secs, you will stop farther.

what he said.

from wht i learn in class, Percision and Reaction time is assumed (from emperical data and safety factor) to be around 2.5 seconds, and design speed of a vehicle's deceleration is about 3.5 m/s^2, regardless the type of vehicles (to answer your question, heavier vehicles just needs a better braking device)

Roads designs are commonly based on that (from AASHTO)

Whatever that youre thinking of has already been thought of and is already taken into consideration in road designs

[laptop-tech]

I'm really concerned about airplanes, as they travel much faster than cars...so they should have even lower speed limits.

[Bortman]

Semi's have a longer time to stop, shouldn't they have a slower speed limit too? Simply put, no. Learn to drive the vehicle properly, stop being an idiot and there should be no problem. (not directed at you, just a general statement)

[FastFokker]

I'm really concerned about airplanes, as they travel much faster than cars...so they should have even lower speed limits.Perhaps you are unaware, but aircraft actually do have speed limits.

Although, if you bust the speed limit, I doubt you only get a speeding ticket.

[Tiberius]

I immediately thought of the transport truck issue as others have mentioned... I guess their speed limit would be really low? :lol:

But... my FAVORITE flaw in the premise of this thread is... the traffic jam / chaos this would create on roads!!! Just imagine all of the trucks/suvs clogging up traffic as they putter along at their slower speed limits... :twisted:

I guess we need completely different highway and road systems dedicated to each type of vehicle, eh? ;) :lol: :twisted:

[divx]

Just wait for someone to invent teleportation and all these problems goes away.

[Badman]

This would only cause more traffic hold ups. Each car going its own speed and slowing down the faster ones in the lane.

But if this was to happen, imagine having a Ferrari, or some really light car ;)

[Nyte]

Definitely not.

But I keep thinking that they should limit them (SUVs, vans, buses, etc) to the right or center lanes as transports are.

[FastFokker]

But I keep thinking that they should limit them (SUVs, vans, buses, etc) to the right or center lanes as transports are.Based on what reasoning?

[rc51]

I like this thought process....:D

Since my RVT1000 can pretty much stop on a dime..it should have a much higher speed limit...regardless of speed I can outbrake anything else on the road except other rockets such as the GSXR1100 or R1 and similar.

[dark169]

of cousre the origonal post doesnt take into accoutn that large trucks/suvs have larger brakes and tires...

If anything we need the abilty to remove old clunkers off the road, new cars/trucks/suvs are safer and ca nsurvuve higher speed impacts, if the clunkers where gone you could boost speed limits.
But then again we let any moron drive in this country, make the abilty to drive a prereq for getting behind the wheel...

[stockbones]

exactly....larger vehicles have bigger brakes to compensate for its size.

of cousre the origonal post doesnt take into accoutn that large trucks/suvs have larger brakes and tires...

If anything we need the abilty to remove old clunkers off the road, new cars/trucks/suvs are safer and ca nsurvuve higher speed impacts, if the clunkers where gone you could boost speed limits.
But then again we let any moron drive in this country, make the abilty to drive a prereq for getting behind the wheel...

[Nyte]

Based on what reasoning?

1) As an incentive to drive smaller more fuel efficient vehicles.
2) Relating back to the original post, these lanes generally have slower speeds, not that I think driving slower would help them too much for braking.
3) And well, what reason do they have for stopping transports from using the left lane?
4) Not really a real point to argue, but I just hate how large vehicles get in the way and block your entire view.

[FastFokker]

1) As an incentive to drive smaller more fuel efficient vehicles. There must be better methods.

What about vehicles which are a cross between a car and SUV?
2) Relating back to the original post, these lanes generally have slower speeds, not that I think driving slower would help them too much for braking.Which lanes have slower speeds? I am unaware of a stretch of road which has different speeds for different lanes.
3) And well, what reason do they have for stopping transports from using the left lane? They don't stop them.. a transport CAN go in the left lane, it's just supposed to remain as far to the right when possible.
4) Not really a real point to argue, but I just hate how large vehicles get in the way and block your entire view.Umm.. you are driving too close then, back off. Use the 2 second rule (at least).

[Nyte]

There must be better methods.

What about vehicles which are a cross between a car and SUV?

Not sure.


Which lanes have slower speeds? I am unaware of a stretch of road which has different speeds for different lanes.

They don't have different speeds as far as limits go, but traffic in the left lane will almost always be traveling faster than on the right, you can see this on any highway.


They don't stop them.. a transport CAN go in the left lane, it's just supposed to remain as far to the right when possible.

Maybe I'm wrong on this, but I've seen lots of signs before that say no transports on the lane. Or maybe this is only some areas then.


Umm.. you are driving too close then, back off. Use the 2 second rule (at least).
Ok, maybe Im not quite explaining this very well, they stop you from seeing the car(s) in front of them. So yes, it forces you to drive a lot farther back from them to be safe. It also removes your ability to predict how the traffic ahead will react, at least on a straight road.

[Nyte]

exactly....larger vehicles have bigger brakes to compensate for its size.

Not arguing about the safety of them, but it doesn't matter how much bigger their brakes are, they are going to have a greater stopping distance...

[Neb]

Changing it won't help SUVs avoid more accidents. They should just be banned from the road IMHO. Most of them are over confident in the winter time, and because of the mass they do not feel the speed they are travelling and think they are invincible.

[D-3vil]

Ok, maybe Im not quite explaining this very well, they stop you from seeing the car(s) in front of them. So yes, it forces you to drive a lot farther back from them to be safe. It also removes your ability to predict how the traffic ahead will react, at least on a straight road.

It's actually safer to drive behind a truck (well, a loaded one at least, and not considering any rocks that may be thrown by the bigger wheels etc). Since trucks have less stopping / accelerating power than most other cars on the road (relative to their size), truck drivers then to be more constant in the way they drive. That means they'll brake early (and smoothly) and accelerate slowly, which in turn allows for a higher reaction time for the cars behind them.

Granted though, it's not much of a view.

[sixer]

SUVS should just be banned outright.

[Nyte]

It's actually safer to drive behind a truck (well, a loaded one at least, and not considering any rocks that may be thrown by the bigger wheels etc). Since trucks have less stopping / accelerating power than most other cars on the road (relative to their size), truck drivers then to be more constant in the way they drive. That means they'll brake early (and smoothly) and accelerate slowly, which in turn allows for a higher reaction time for the cars behind them.

Granted though, it's not much of a view.

Yes, but at the same time, you are still forced to drive much farther back from them if you want to be safe. Sure you can follow them closely, but if they brake hard and you aren't expecting it, you in turn brake even harder, what about the person behind you...

Also, if I can't tell what's in front of them, how do I know if they're just driving slow and blocking traffic, and thus, I might want to pass, or if there are cars in front of them.

[KelticSlob]

I'm in favour of banning Trucks/SUV's entirely. You have to prove that you need a truck/SUV for work purposes to use them.

I don't think their speed limits should be reduced, though. They drive slow enough already.

[mbg]

Semi's have a longer time to stop, shouldn't they have a slower speed limit too?

They do have lower speed limits for HGVs (Heavy Goods Vehicles) in England...

[FastFokker]

Sure you can follow them closely, but if they brake hard and you aren't expecting it, you in turn brake even harder, what about the person behind you...Yes, you should always be following behind at a safe distance.

Also, you should always be paying attention and expecting the unexpected. A lazy, inattentive driver is a bigger hazard than ANY oversized vehicle on the road.
Also, if I can't tell what's in front of them, how do I know if they're just driving slow and blocking traffic, and thus, I might want to pass, or if there are cars in front of them.It's called easing to the left to peak past them.

That's why we drive on the right and sit on the left.

As you ease over, if you see someone coming you get back.. if the passing lane is clear, it is time for you to proceed.

Now if you are requiring the trucks to drive slower, just think about how much more often you will be forced to pass them.. passing isn't safe, no matter how big the vehicle is.
They do have lower speed limits for HGVs (Heavy Goods Vehicles) in England...You should notify your provincial Ministry of Transportation of your findings.

[galanz]

In real life, vehicles stop the same.. (generalized)



Uhmm I hope you're kidding.

http://www.nhtsa.dot.gov/cars/testing/brakes/

100KM/H stopping distances

Ford Expedition 170.4
Toyota Camry LE 159.7
Chevy Malibu LS 141.3
Dodge Ram 1500 4x4 199.2
Pontiac Bonneville 156.7

~58 feet further for the Dodge to stop over the Malibu, which would you rather have behind you on the highway when you need to make an emergency stop?

[galanz]

They do have lower speed limits for HGVs (Heavy Goods Vehicles) in England...

It wasn't that long ago they had different speed limits in Canada as well.

[hyperion]

An incentive to stop driving SUVs, that'd be awsome. Not gonna happen though.

[FastFokker]

Uhmm I hope you're kidding.

http://www.nhtsa.dot.gov/cars/testing/brakes/

100KM/H stopping distances

Ford Expedition 170.4
Toyota Camry LE 159.7
Chevy Malibu LS 141.3
Dodge Ram 1500 4x4 199.2
Pontiac Bonneville 156.7

~58 feet further for the Dodge to stop over the Malibu, which would you rather have behind you on the highway when you need to make an emergency stop?Apparently you missed my point.

58feet is not much. Do you realize how many feet you travel in 1second going 100km/h? A hesitation of 1second longer doing highway speeds is more critical than published data from manufacturers of stopping distances.

*GENERALLY* vehicles stop the same.. yes, within a matter of meters differences, but that's under controlled conditions with a professional driver who is ready to stop the vehicle as quick as possible.

No commuter on the 400 series highway would fit that criteria.

[FastFokker]

I did the conversion.. 100km/h = 27.78m/s

So a hesitation of merely ONE SECOND will result under published manufacturer stopping distances of an addition by 28meters or 91feet.

[Neb]

If you are talking about reaction time, then cell phones, radios, navs, etc all shoudl be banned, we shoudl all focus on the car infront of us.

The stopping distance even if it's 1 meter will result in either collision or a near miss. Assuming all the people driving on the 400 have the same reaction time, distracted by whatever, if all of us slam on our brakes simultaneously, the person driving the SUV/truck will hit the one in front. So the arguement I think stands for that SUVs and TRUCKs have longer stopping distances, it's a FACT.

end of arguement.

[FastFokker]

end of arguement.Not so fast.If you are talking about reaction time, then cell phones, radios, navs, etc all shoudl be banned, we shoudl all focus on the car infront of us. Exactly, cell phones, wandering eyes, messing with radio, talking to passengers, eating, daydreaming..etc they all are going to impact your reaction time and that is the most critical point, rather than the detailed manufacturers published stopping distances for a vehicle, again which is done by a professional driver under very controlled environments.
The stopping distance even if it's 1 meter is a matter of a collision or not.Not really, there is another method called avoidance. It's where instead of hitting the vehicle in front of you, you maneuver around them.. that's a great benefit of ABS, it still allows you to maneuver.

Published data on stopping distances means nothing to the average driver, other than giving them some kind of false sense of security because their vehicle *CAN* stop faster than others.

Since not all drivers are the same and not all drivers are good drivers and not all vehicles braking systems are in top condition and not all people have good tires on their vehicles and not all drivers have the same reaction time, we might as well throw out the manufacturers data on stopping distances as it's useless.

[galanz]

Apparently you missed my point.

58feet is not much. Do you realize how many feet you travel in 1second going 100km/h? A hesitation of 1second longer doing highway speeds is more critical than published data from manufacturers of stopping distances.

*GENERALLY* vehicles stop the same.. yes, within a matter of meters differences, but that's under controlled conditions with a professional driver who is ready to stop the vehicle as quick as possible.

No commuter on the 400 series highway would fit that criteria.

58 feet not much? It just takes just over 33% further to stop, yeah, not much at all. So that extra 1 second hesitation would affect both vehicles equally wouldn't it? And the Dodge is still an extra 58 feet down the road assuming it didn't run into anything(big assumption).

Now if you would care to backup this statement "*GENERALLY* vehicles stop the same.. yes, within a matter of meters" with facts I might reconsider my opinion. As it stands both logic and the NHTSA say you're wrong. :lol:

[galanz]

Not really, there is another method called avoidance. It's where instead of hitting the vehicle in front of you, you maneuver around them..


Good point, another way that the heavier less manouverable trucks and suvs are more dangerous than cars.

[FastFokker]

58 feet not much? It just takes just over 33% further to stop, yeah, not much at all.Yes that is a good number.. 58 feet is 58 feet, it's real, I understand that. But it's not a real number attainable by everyone in the same vehicle in the same environment. So what does it really mean?

It's the same as 1/4mile times (just opposite)... Yes, it's attainable, but will you get the same number as the professional driver in a controlled environment? No. Will your grandma get it? No.
So that extra 1 second hesitation would affect both vehicles equally wouldn't it?No, and perhaps this is the point you are fundamentally missing. Some people have very quick reaction times and are paying better attention to the road, while others are not.. the hesitation/response/reaction time is independant of vehicle.

It doesn't matter if you're driving a Ferrari that will stop in 50feet, if you aren't watching the road you will smash into the vehicle in front of you.
Now if you would care to backup this statement "*GENERALLY* vehicles stop the same.. yes, within a matter of meters" with facts I might reconsider my opinion. As it stands both logic and the NHTSA say you're wrong. :lol:I'm not saying the actual data numbers are the same, I'm saying let's just ignore the data as it's useless.. and instead we'll generalize that car/motorcycle/truck/van/suv all stop about the same, because there's just too many variables included in every situation for us to even have this conversation, we must generalize or the debate ends as it's dependent on the entire situation.

Another point not mentioned is that vehicles do not drive at the same speed to begin with... check out the stopping distance from 50km/h, 80km/h, 110km/h and 140km/h, it won't be linear.

Staggering speeds is dangerous, if everyone is going the exact same speed, it's the most safe.

[cliff]

58feet is not much. Do you realize how many feet you travel in 1second going 100km/h? A hesitation of 1second longer doing highway speeds is more critical than published data from manufacturers of stopping distances.
58 feet is ~3 car lengths. That is a major difference. How many accidents have happened where drivers have though "if only I had 5 more feet" this is 10 times that.

Independent of the drivers ability in whichever car they are driving, 58 feet will often be the difference between contact and complete avoidance of an accident.

Are you trying to say people driving heavier vehicles are inherently more attentive while driving then those that drive vehicles that stop faster?

[FastFokker]

Perhaps I am not understanding what you guys are getting at, or I'm just completely off my rocker.

Ford Expedition 170.4
Toyota Camry LE 159.7 :arrowl: Car stops ~10ft sooner than SUV.

Isn't the saying that as speed doubles, stopping distance quadruples?

All vehicles should therefore be slowed if we care so much about stopping distance numbers. 100km/h is too fast, all vehicles should do ~60km/h. :rolleyes:

Requiring SUV's to drive slower as a reason for safety just makes *NO* sense in my head.

[manho]

if a SUV has follow the 2 seconds rule from bumper to bumper, @100km/h, he would be 55.56m behind the car in front of him. (100 / 3.6 * 2)

Assuming the car in front hard brake out of no where (@ a deceleration rate of 8 m/s2), but the SUV driver took the entire 2 seconds to react, their gap is closed to 55.56m - 39.52m = 16.04m

(v=v0+at=100/3.6- 8*1=11.77m/s, d = (v1^2-v2^2)/2a = 39.52m)

In order to collide, the SUV's braking ability must have a stopping distance of 16.04m worst than the car in front of it

However, from the site, the range of the braking distances varies from 47m to 42.9m, and tats only 4.1m, which is 4 times the 16m of available stopping distance differences.

That being said, the worst performed vehicle in the braking test is still safe on the road since it still have a safety factor of 4, which is sufficient in this scenario

[frogger]

Yes and 18 wheelers and buses shouldhave 50km/hr limits on the highway. I think all cars should be tested since a car with 3 year old brakes will have diminished braking performance and should have lower speed limits too. Older cars too.
Lets completely remove any driver judgement regarding following distances from the mix and just make for more interesting lane changes.

[manho]

Requiring SUV's to drive slower as a reason for safety just makes *NO* sense in my head.

it really is just an image bias.

just like how people back in the old days thinks heavier object falls faster, hence everything falls at 9.8m/s^2

the difference is, it takes more effort (energy) to stop a heavier object. but the effort is there in the braking devices, as well as in tires.

[galanz]

Yes that is a good number.. 58 feet is 58 feet, it's real, I understand that. But it's not a real number attainable by everyone in the same vehicle in the same environment. So what does it really mean?

It's the same as 1/4mile times (just opposite)... Yes, it's attainable, but will you get the same number as the professional driver in a controlled environment? No. Will your grandma get it? No.
No, and perhaps this is the point you are fundamentally missing. Some people have very quick reaction times and are paying better attention to the road, while others are not.. the hesitation/response/reaction time is independant of vehicle.

It doesn't matter if you're driving a Ferrari that will stop in 50feet, if you aren't watching the road you will smash into the vehicle in front of you.
I'm not saying the actual data numbers are the same, I'm saying let's just ignore the data as it's useless.. and instead we'll generalize that car/motorcycle/truck/van/suv all stop about the same, because there's just too many variables included in every situation for us to even have this conversation, we must generalize or the debate ends as it's dependent on the entire situation.

Another point not mentioned is that vehicles do not drive at the same speed to begin with... check out the stopping distance from 50km/h, 80km/h, 110km/h and 140km/h, it won't be linear.

Staggering speeds is dangerous, if everyone is going the exact same speed, it's the most safe.

The whole point of this argument is which vehicle is safer given similar conditions. I'm sure no one would argue that Michael Schumacher in a Porsche Cayenne is safer than you driving a Beetle, but that's not the point here. Vehicles that are proven to stop shorter(I'm still waiting for you to prove that all vehicles stop in the same distance) are going to be safer for everyone. This is undeniable, to say that stopping distances are 'useless' is honestly quite scary.

[galanz]

58 feet is ~3 car lengths. That is a major difference. How many accidents have happened where drivers have though "if only I had 5 more feet" this is 10 times that.

You also have to think about how fast that Dodge is still going to skid an extra 58 feet past the Malibu. It would be interesting to see how much momentum it would still have at that point. I just know I wouldn't want to be in front of it.

[FastFokker]

http://www.nhtsa.dot.gov/cars/testing/brakes/

Here's real numbers from the test, ordered from best to worst w/payload:

Pontiac Grand Am 46.3m
Chevy Malibu 47.0m
Toyota Camry 49.2m
Pontiac Bonneville 49.7m
Cadillac DeVille 50.4m
Ford Expedition 51.5m
Dodge Caravan 52.8m
Chevrolet Express 1ton 55.0m
Chevrolet Astro 55.9m
Dodge Ram 1500 57.5m

:arrowu: Cadillac DeVille (a car) only stops ~1m prior to the Ford Expedition (SUV).

It's interesting if you look, for example the Dodge Ram 1500 & Ford Expedition actually stop quicker with a full payload, than they do without payload, you see there is much more to it than just weight, as in that case, WEIGHT HELPS.

Dodge Ram 1500 60.7 (Empty)
Dodge Ram 1500 57.5m (Loaded)

Ford Expedition 52.0m (Empty)
Ford Expedition 51.5m (Loaded)

[galanz]

the difference is, it takes more effort (energy) to stop a heavier object. but the effort is there in the braking devices, as well as in tires.

No, the difference is that I've already posted data that proves that these vehicles take longer to stop. The higher accident rate for suv's proves this.

[Evil Techie]

obviously SUV are designed to have bigger brakes

anyone who is upping their rim size to more than 19" should seriously consider big brake kits as the rolling weight is really hard for the original brake kits to stop

[FastFokker]

No, the difference is that I've already posted data that proves that these vehicles take longer to stop. The higher accident rate for suv's proves this.Sorry, I just blew your "data that proves" out of the water, showing that in some instances, a heavier vehicle actually stops quicker.

Also, your ~58ft differential from best to worst is gone as well.

[galanz]

http://www.nhtsa.dot.gov/cars/testing/brakes/

Here's real numbers from the test, ordered from best to worst w/payload:

Pontiac Grand Am 46.3m
Chevy Malibu 47.0m
Toyota Camry 49.2m
Pontiac Bonneville 49.7m
Cadillac DeVille 50.4m
Ford Expedition 51.5m
Dodge Caravan 52.8m
Chevrolet Express 1ton 55.0m
Chevrolet Astro 55.9m
Dodge Ram 1500 57.5m

:arrowu: Cadillac DeVille (a car) only stops ~1m prior to the Ford Expedition (SUV).

It's interesting if you look, for example the Dodge Ram 1500 & Ford Expedition actually stop quicker with a full payload, than they do without payload, you see there is much more to it than just weight, as in that case, WEIGHT HELPS.

Dodge Ram 1500 60.7 (Empty)
Dodge Ram 1500 57.5m (Loaded)

Ford Expedition 52.0m (Empty)
Ford Expedition 51.5m (Loaded)

Aha, now you're admitting now that all vehicles Don't stop in the same distance. Progress! :)

[actng]

some of you troll way too soon.

1. smokers do pay more in some cases for health insurance. sometimes they also pay more in the sense that their coverages are denied by some insurers. at my work, smokers pay a higher premium / receive lower benefits payouts.

2. semis do take longer to stop. although they don't have a lower speed limit, there is a more conservative best practice. ever notice they leave TONS of room in front of them? the 18 wheelers try to slow / stop the vehicle more than they need to. this is partly to compensate for the more room required to slow down / stop but also to compensate for the increased time it takes to speed up when traffic gets moving again.


I think we should be more positive. instead of restricting the speed limit for SUVs and other vehicles that take longer to stop, we should raise the speed limit for cars that are able to stop quicker.

An Aston Martin DB9 can stop in half the distance of a normal car. Therefore DB9s should be able to go twice as fast. :cheesygri

[galanz]

Sorry, I just blew your "data that proves" out of the water, showing that in some instances, a heavier vehicle actually stops quicker.

Also, your ~58ft differential from best to worst is gone as well.

Heheh, not at all. Most trucks are relatively light in the rear, balancing the weight out will help their braking. But their braking distances are still longer than the cars. Thanks for trying. At least you've stopped claiming all vehicles stop in the same distance. It's good to see you're coming around.

[FastFokker]

Aha, now you're admitting now that all vehicles Don't stop in the same distance. Progress! :)Actually, I've been claiming that all along.. and for MANY reasons they don't stop in the same distance.

Seriously, am I talking to myself?Heheh, not at all. Most trucks are relatively light in the rear, balancing the weight out will help their braking. But their braking distances are still longer than the cars. Thanks for trying. At least you've stopped claiming all vehicles stop in the same distance. It's good to see you're coming around.If you read the post you are referring to I said:
In real life, vehicles stop the same.. (generalized)I am STILL saying that.. we must generalize to even have this conversation.

If you want to get into the details, we'll conclude the same thing provincial Ministry of Transportation's have, that there is no valid reason to slow SUV's over cars.

[galanz]

I think we should be more positive. instead of restricting the speed limit for SUVs and other vehicles that take longer to stop, we should raise the speed limit for cars that are able to stop quicker.

Now you're talking. I could go for that.

[galanz]

Actually, I've been claiming that all along.. and for MANY reasons they don't stop in the same distance.

Seriously, am I talking to myself?If you read the post you are referring to I said:
I am STILL saying that.. we must generalize to even have this conversation.

If you want to get into the details, we'll conclude the same thing provincial MTO's have, that there is no valid reason to slow SUV's over cars.

Did you not post this? If not someone's haXXor3d your account.


In real life, vehicles stop the same.. (generalized)

[FastFokker]

*bangs head on keyboard*

Note the "in real life" and the "(generalized)".

Yes again, numbers are numbers and under certain tests some vehicles do better than others, but it's not so clear cut as to say SUV's always stop MUCH farther than cars. That's just wrong!

There is absolutely no sense in an implimentation of staggering speeds between "cars" and "suv/trucks/vans". Differences in speed is what CAUSES more accidents, not stopping distances.

Stopping distances are an after thought.

[jdi_knght]

While I have no love for SUVs, I don't think requiring a lower speed limit for them makes a heck of a lot of sense. Yes, in general, all conditions being equal, an SUV will often take longer to stop than a regular passenger car.

But if you start requiring a lower speed limit because of the weight, what next?

Lower speed limit for..?

vehicles driven during the winter months that are not equipped with winter tires
lower speed limit for drivers over the age of __ since reaction speed usually decreases with age
vehicles with 'budget' brakes or brakes that have not been replaced within the last __ years
vehicles with a weight over __ including passengers


All of the above factors will typically result in a longer stopping distance, but where would you draw the line? The fact is, in the dead middle of winter, if I have terrible summer tires (or 'all season' tires) on a little sprint/firefly/swift/metro, I could very well take much longer to stop than a massive SUV with excellent brakes, studded winter drivers, and an alert driver with fast reaction speed.

Not only that, but as soon as there are differences in speed limits, you're probably going to increase collisions in some areas. For example the stretch between Manitoba and Kenora which has 1 lane each direction. If SUVs were required to travel slower, you would have an increased amount of traffic passing, and almost certainly an increase in head-on collisions.

In short, I don't think you could justify lower speed limits for SUVs based on them taking longer to stop. Not in most of Canada anyway. There are many other factors that come into play, and aside from it not being 'fair', it just doesn't make a whole lot of sense.

[galanz]

*bangs head on keyboard*

Note the "in real life" and the "(generalized)".

Yes again, numbers are numbers and under certain tests some vehicles do better than others, but it's not so clear cut as to say SUV's always stop MUCH farther than cars. That's just wrong!

There is absolutely no sense in an implimentation of staggering speeds between "cars" and "suv/trucks/vans". Differences in speed is what CAUSES more accidents, not stopping distances.

Stopping distances are an after thought.

Dude seriously you need to figure out what you're trying to claim here. First you state that "in real life" vehicles stop in the same distance(which I'm still waiting for you to prove), then you say they don't actually stop in the same distance. Pick a side seriously, watching you spin like that is starting to make me dizzy.

[jason9945]

They do have lower speed limits for HGVs (Heavy Goods Vehicles) in England...
Somebody should point out that 18 wheelers/ busses etc are driven by TRAINED drivers. These are professional drivers, not soccer moms who feel invincible in their trail blazer (blazing a trail to walmart no doubt)

[FastFokker]

Dude seriously you need to figure out what you're trying to claim here. First you state that "in real life" vehicles stop in the same distance(which I'm still waiting for you to prove), then you say they don't actually stop in the same distance. Pick a side seriously, watching you spin like that is starting to make me dizzy.No, I didn't say they stop in the same distance.

No offense, but you are spinning either by your own choice, because you refuse to comprehend what I am saying or you just honestly can't comprehend what I'm saying.

In order to debate this, we must generalize that in real life vehicles stop the same.. otherwise, if we get into the details, they are *VERY* extensive and considering this method of debate, we would never get anywhere as the details ALONE would bog us down.

Best bet here is to trust our governments decision that equal speed limitations for all vehicles is the safest idea. Or read some good posts written by jdi_knght, manho and others.

[galanz]

No, I didn't say they stop in the same distance.


Uhmm Yes you did.

In order to debate this, we must generalize that in real life vehicles stop the same..

No we don't. Why you ask? Because they quite simply don't, that's the whole point here.

[FastFokker]

Uhmm Yes you did.In real life, vehicles stop the same.. (generalized)Do you have data on real life stopping distances of different vehicles and different drivers in different weather conditions using non-OEM hardware on their vehicles, among other differences, which can dispute that claim?

I suspect you don't.

So in real life, vehicles stop the same.. (generalized)

[DJ_Peanuts22]

if you are referring to top speed, then yes, most SUV's are electronically governed to lower top speeds, usually around 100mph/160km/hr, whereas most cars are higher

[galanz]

So in real life, vehicles stop the same.. (generalized)

So now you once again claim that vehicles stop the same. Jeez dude, seriously pick a side.
I've asked you to prove this three times now as I've posted proof that they don't. All I'm asking(besides sticking to one argument) is to back your claims with facts as I've done. Or keep spinning and looking sillier and sillier, your choice.

[FastFokker]

galanz, obviously you're just playing games here while on March Break.

[galanz]

galanz, obviously you're just playing games here while on March Break.

Heheh, pot meet kettle.

:lol:

[manho]

let's put it this way

Generally, say in road design criteria, the design speed (or vehicle performance) of the road is generalized, for the easier sake of calculation. Meaning, we generalize the stopping distance distance of vehicles from emperical data.

In real life, even if SUV in general do require a longer stopping distance, i just doubt it makes a significant difference in accident rates.

No, the difference is that I've already posted data that proves that these vehicles take longer to stop. The higher accident rate for suv's proves this.

now you have to take other things into factor for the accident rate thing. like higher ride height. i remember when i was 16 and almost flipped my CRV by trying to swing it like a civic. lol. and remember the old expedition that was recalled because it flips. yikes

as well, i do agree that SUV drivers think theyre king of the road when its snowing. and i mean, that's really wrong. people dont understand that braking performance has nothing to do at all with the extra set of axle wheel power

all in all, you cant directly correlate the accident rates with stopping distance. it could be a variable, but does it play a significant role in it? i really doubt it.

[pandaharo]

No, 99.99% of the time is the drivers fault.

[mbg]

Not really, there is another method called avoidance. It's where instead of hitting the vehicle in front of you, you maneuver around them.. that's a great benefit of ABS, it still allows you to maneuver.

And, ability to avoid is reduced in an SUV due to the extra weight and high centre of gravity. They provide passive rather than active safety, and they increase risk to everyone around them.

[mbg]

No, 99.99% of the time is the drivers fault.

And deciding what kind of car to drive is a driver's decision, too :)

[FastFokker]

Latest news:

http://news.moneycentral.msn.com/provider/providerarticle.asp?feed=AP&Date=20060317&ID=5556304
Seven SUV's and one pickup earn top marks in crash tests
WASHINGTON (AP) - Seven sport utility vehicles have earned the highest ratings in the latest government crash tests.

They all received five stars in front-end and side impact tests, for both the driver's and passenger's sides. The seven models are 2006 Ford Explorer, Honda Pilot, Hyundai Tucson, Mercedes Benz M-L-class, Nissan Murano and Subaru B-nine Tribeca.

[Nyte]

Yes, you should always be following behind at a safe distance.

Also, you should always be paying attention and expecting the unexpected. A lazy, inattentive driver is a bigger hazard than ANY oversized vehicle on the road.

Im not completely sure if you got what I mean...


It's called easing to the left to peak past them.

That's why we drive on the right and sit on the left.

As you ease over, if you see someone coming you get back.. if the passing lane is clear, it is time for you to proceed.

Now if you are requiring the trucks to drive slower, just think about how much more often you will be forced to pass them.. passing isn't safe, no matter how big the vehicle is.

What passing lane? Im talking about them already driving in the left (passing) lane. Yes, you can move a bit over onto the shoulder to look, but should you really be required to do that?

[FastFokker]

What passing lane? Im talking about them already driving in the left (passing) lane. Yes, you can move a bit over onto the shoulder to look, but should you really be required to do that?Well if it's a 4 lane highway, then the trucks are required to stay on the right, except when passing. So the left most lane is there for you to pass.

If it's a 2 lane highway, then you are to pass in the oncoming lane, so long as the road and traffic allows. That is the passing lane I'm referring to, the oncoming traffic lane. To peak around a large vehicle, you ease to the left slowly to view if it is clear to pass, if it is.. you go!

As stated before, if you require more vehicles to drive slower than other vehicles, consider the increased number of passes required.. passing using the oncoming traffic lane is dangerous and it doesn't matter how fast your vehicle can brake, a head on collision is extreme.

[Nyte]

Latest news:

http://news.moneycentral.msn.com/provider/providerarticle.asp?feed=AP&Date=20060317&ID=5556304
Seven SUV's and one pickup earn top marks in crash tests

Who cares what their crash ratings are? No-one is saying they can't survive a crash. I could drive a tank or something and survive your SUV crashing into me too.

[FastFokker]

Who cares what their crash ratings are? No-one is saying they can't survive a crash. I could drive a tank or something and survive your SUV crashing into me too.Seriously?

You're telling me you don't care about crash ratings, but you care deeply about manufacturers published stopping distances by a professional driver under controlled variables?

May I indulge, how many years driving experience you have?

[Nyte]

Well if it's a 4 lane highway, then the trucks are required to stay on the right, except when passing. So the left most lane is there for you to pass.

If it's a 2 lane highway, then you are to pass in the oncoming lane, so long as the road and traffic allows. That is the passing lane I'm referring to, the oncoming traffic lane. To peak around a large vehicle, you ease to the left slowly to view if it is clear to pass, if it is.. you go!

As stated before, if you require more vehicles to drive slower than other vehicles, consider the increased number of passes required.. passing using the oncoming traffic lane is dangerous and it doesn't matter how fast your vehicle can brake, a head on collision is extreme.

Yes.. you're stating the obvious...
In case you forgot, Im not arguing that trucks should have a lower speed limit, Im saying they (and SUVs, vans, etc) should stay to the right.
And FYI, Im thinking 6 lane highways here.

[Nyte]

Seriously?

You're telling me you don't care about crash ratings, but you care deeply about manufacturers published stopping distances by a professional driver under controlled variables?

May I indulge, how many years driving experience you have?

No, what I mean is that they have nothing to do with the topic we are discussing.

[manho]

No, what I mean is that they have nothing to do with the topic we are discussing.

what he said

[FastFokker]

Alright, well the article had to do with SUV's and this thread is about SUV's.. my apologies for offending you all with information that doesn't cater to your personal interests.. I presumed those not interested could just skip it, my apologies!

Honestly I dislike SUV's, so I don't want to give the illusion of being in defense of SUV's, but I just don't see any rationality to restricting SUV speeds based on stopping distances.

I think most of the rational and logical points have been raised.

[Nyte]

Honestly I dislike SUV's, so I don't want to give the illusion of being in defense of SUV's, but I just don't see any rationality to restricting SUV speeds based on stopping distances.


There are a lot more negatives to SUVs than just stopping distances...

[FastFokker]

There are a lot more negatives to SUVs than just stopping distances...Yes, but as you specified, nothing other than stopping distances is allowed to be discussed in this thread.No, what I mean is that they have nothing to do with the topic we are discussing.In any event, the blanket statement in the thread title "SUV's take longer to stop" is just flawed, it doesn't even state what they take longer THAN. :confused:

Even if all SUV's did take longer to stop than all cars, it still doesn't stand to good reasoning to require SUV's to drive slower than the rest of traffic on the road. That will only cause more accidents and negate any benefits of the better stopping distances.

Again, stopping distances are an after thought.. a rear-end collision @ ~20km/h is not fatal. Requiring SUVs to drive slower will require more vehicles to pass them.. head on collisions are deadly.

[wylie]

Longer stopping distances for SUV's + better front end damage/safety = disturbing news for small car drivers.
If I ever get rear ended by an SUV with my child in the back seat of my car, someone will have to hold me back because I think I would beat the living sh*t out of the driver -male or female.

Nobody needs an SUV, maybe only .1%

[FastFokker]

What about motorcyclists?

Doesn't matter if it's a car, van, truck or suv hitting them.. it all hurts the same.

For the sake of motorcyclists, I guess if they ever get hit by a car, they should also do what you say you would do to an SUV driver to hits you. You better take good caution you don't strike a motocyclist then.

[wylie]

As being a motorcycle rider, I somewhat agree. The point I was trying to make is that an SUV is an unnessary vehicle and endangers others. A compact car is a neccessity as I would not take my 2 year old on my bike.

Also if you are a good motorcycle rider, you should be able to avoid being hit from behind as you can manuever a bike much quicker and more aggressivly.

[FastFokker]

What about people who don't want a van, but need something more than a car (for capacity)?

If a truck rearended you, would you feel the same? What about a van?
Also if you are a good motorcycle rider, you should be able to avoid being hit from behind as you can manuever a bike much quicker and more aggressivly.If you are a good car driver, you should be able to avoid being hit from behind as you can manuever a car much quicker and more aggressively than a heavier, larger vehicle. ;)

[wylie]

A minivan is great (I have one for hauling everything), which is heavier than a car does have bumpers at the same level as cars which would help in an accident. An SUV has their bumbers higher up which would cause more damage. An SUV has no more capacity than a good wagon. (eg Freelander or Subaru with the bonus of all wheel drive too)

A car cannot move as quickly as a motorcycle and if you are on a multilane road you cannot go between cars like you can on a bike at lets say a stop light.

The bottom line is I would be pissed if anyone rearended me, but would be more concerned about an SUV.

[FastFokker]

A car cannot move as quickly as a motorcycleNeither a car nor a motorcycle will do anything without an operator.

Appears the onus is on the driver/rider.

I've own a crotch rocket before as well, so I get what you're saying.. but when driving my car, I am constantly watching behind me for people not paying attention.. perhaps that was derived from my years on a bike.

[wylie]

Where I live in Mississauga, I always make sure to stay far away from any Corolla, as Corolla drivers seen to be the worst drivers in town :lol:

[Neb]

Where I live in Mississauga, I always make sure to stay far away from any Corolla, as Corolla drivers seen to be the worst drivers in town :lol:

AHHAHA... tha'ts forsure. I joke with my fiancee about it all the time, she had a corolla ;) haha..

There was a thread on this a while back, the tan/gold color ones are the worst.

Ok back to teh thread, SUV ins are higher, they are higher risk than a car, and also they can do more damage, probably why the rate is higher. Either way, our roads will be alot safer if there were no SUVs on the road. And get a station wagon if u want to haul stuff around.