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CylonRed
Premium,MVM
join:2000-07-06
Bloom County
reply to cahiatt

Re: Jeep Grand Cherokee almost rolls over during maneuver tests

Owning a 3 series - I can't imagine it not needing a good bit of help to do that...



The Pig
I know you want to be me
Premium
join:2009-09-11
reply to Gbcue

In nearly all vehicles, if you try to turn really fast circles (doughnuts) to try to rollover a vehicle, the tires nearly always break free of the pavement before enough side force can be produced. But when a vehicle is already traveling at speed, and a sudden and extreme side turn is made, the tire traction can exist long enough to cause a rollover. This is related to the fact that there are two different frictional coefficients between the tires and the roadway. A STATIC coefficient of friction is usually slightly higher than the DYNAMIC coefficient of friction. As long as traction is maintained, then the higher STATIC value applies, but as soon as the tires start sliding, the lower DYNAMIC value applies.

»mb-soft.com/public/rollover.html



MEDIAN2k3
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join:2002-12-04
united state
kudos:1
reply to Gbcue

My friend just flipped her civic ironically....



CylonRed
Premium,MVM
join:2000-07-06
Bloom County

How did she do that????



MEDIAN2k3
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join:2002-12-04
united state
kudos:1
reply to Gbcue

Umm I believe she hit a turn going like 50 and then lost control into a ditch



CylonRed
Premium,MVM
join:2000-07-06
Bloom County

Ahhh - the ditch rolled the car... she was not hurt I take it?



MEDIAN2k3
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join:2002-12-04
united state
kudos:1
reply to Gbcue

Few scratches and bruises. Nothing bad, car got it worse.



The Pig
I know you want to be me
Premium
join:2009-09-11
reply to Gbcue

Keep using those seatbelts no matter what you drive, please!



Anonymous_
Anonymous
Premium
join:2004-06-21
127.0.0.1
kudos:2
reply to Gbcue

too bad it did not say the year



Lurch77
Premium
join:2001-11-22
Oconto, WI
kudos:4

Looking at the video, it is the current generation.


Kearnstd
Space Elf
Premium
join:2002-01-22
Mullica Hill, NJ
kudos:1
reply to Gbcue

any SUV will roll easier than a car due to being higher up and having a higher center of gravity. I bet one could roll any SUV on the market at 40mph with a good wheel crank.
--
[65 Arcanist]Filan(High Elf) Zone: Broadband Reports



Doctor Olds
I Need A Remedy For What's Ailing Me.
Premium,VIP
join:2001-04-19
1970 442 W30
kudos:18

said by Kearnstd:

any SUV will roll easier than a car due to being higher up and having a higher center of gravity. I bet one could roll any SUV on the market at 40mph with a good wheel crank.

Especially when you overload the SUV (like Consumers Union did to the Samurai) and hang two 500 lb outriggers on each front door aka one each on the passenger and drivers doors).
--
What’s the point of owning a supercar if you can’t scare yourself stupid from time to time?

cahiatt
Premium
join:2001-03-21
Smyrna, GA

1 edit
reply to CylonRed

said by CylonRed:

Owning a 3 series - I can't imagine it not needing a good bit of help to do that...

I agree. But it happened and was on a few news clips also. I looked again and cannot find the video anywhere. It was a press reveal for a new 3 series I think around 1998 or so. BMW has probably used copyright take down requests and pulled all the video to keep it from getting too viral.

They brought the car out and were doing some high speed maneuvers. Reverse 180's, slalom, etc... It was absolutely flat ground, no curbs, ramps or other interference. Must have had the perfect combination of traction and weight transfer because on one of the maneuvers the car just went bottom up....

-edit- Still trying to find info. Best I have found so far was that this was in 1997 and it was the introduction of the wagon, not the sedan and it happened while being broadcast on CNN.


CylonRed
Premium,MVM
join:2000-07-06
Bloom County

Having been to many high performance driving schools for the BMW club thru the years - with my Civic and BMW, with many 3 series vehicles (many stock) - I have yet to see a anything even resembling a 3 series on 2 wheels (unless they took a large chunk of curb) much less come close to flipping. This is cars doing 70+ MPH thru the corners and accelerating out.

I would bet a weeks pay - it was some sort of parts failure. In other words - it got a lot of help.

I am going to be doing BMW Street Survival\Car control clinic at Mid-Ohio in Sept - I know the cars are not going to roll unless they get a lot of help.
--
Brian

"It drops into your stomach like a Abrams's tank.... driven by Rosanne Barr..." A. Bourdain


cahiatt
Premium
join:2001-03-21
Smyrna, GA

said by CylonRed:

I would bet a weeks pay - it was some sort of parts failure. In other words - it got a lot of help.

I'm done looking for it and would be of no benefit to me to prove it to you that it happened. Other than your paycheck. I'll PM you my address when you get the info you need.

Anything CAN happen. Next time you are curious ask your BMW buddies if anyone remembers seeing them introduce the 3 (Maybe 5 series) wagon around 1997 and they flipped it during some spirited driving during the reveal.

Kearnstd
Space Elf
Premium
join:2002-01-22
Mullica Hill, NJ
kudos:1
reply to CylonRed

true the 3 series is pretty low. of course the two BMWs I can picture rolling rather easy are the X3 and X5 as they are both SUVs.
--
[65 Arcanist]Filan(High Elf) Zone: Broadband Reports



Doctor Olds
I Need A Remedy For What's Ailing Me.
Premium,VIP
join:2001-04-19
1970 442 W30
kudos:18
reply to cahiatt

said by cahiatt:

said by CylonRed:

I would bet a weeks pay - it was some sort of parts failure. In other words - it got a lot of help.

I'm done looking for it and would be of no benefit to me to prove it to you that it happened. Other than your paycheck. I'll PM you my address when you get the info you need.

Anything CAN happen. Next time you are curious ask your BMW buddies if anyone remembers seeing them introduce the 3 (Maybe 5 series) wagon around 1997 and they flipped it during some spirited driving during the reveal.

I've seen that video and I thought is was a BMW Wagon being introduced that flipped after the driver performed a Rockford maneuver. I looked and can't find that video so far and I spent 30 minutes searching.
--
What’s the point of owning a supercar if you can’t scare yourself stupid from time to time?


Cho Baka
Premium,MVM
join:2000-11-23
there
kudos:2
Reviews:
·TekSavvy DSL

Sure it wasn't the Mercedes A Class:

»www.youtube.com/watch?v=Um-XlKer···=related

--
The talented hawk speaks French.


CylonRed
Premium,MVM
join:2000-07-06
Bloom County
reply to Doctor Olds

Again - it could have been filmed - it is EXCEEDINGLY probable - something broke. The wagons are not that tall, to have that high of a CoG - and the wagons are generally heavier.
--
Brian

"It drops into your stomach like a Abrams's tank.... driven by Rosanne Barr..." A. Bourdain


neonturbo

join:2009-02-27
Lansing, MI

1 recommendation

reply to Doctor Olds

»www.youtube.com/watch?v=ncohOWhKaAU


aurgathor

join:2002-12-01
Lynnwood, WA
kudos:1
Reviews:
·Frontier Communi..

I guess if someone tries it 'hard enough', or there are minor imperfections in the road, most anything can be rolled over with some 'luck' and persistence.
--
Wacky Races 2012!



Insight6

join:2012-08-25

1 edit
reply to Gbcue

It's mostly about the ratio of sprung vs unsprung weight. Vans and most SUVs have proportionately a lot more sprung weight.

Then the load in the vehicle, center of mass and tires can contribute to make the rollover potential or ease to rollover even greater.

Vehicles like vans and most SUVs are physically more vulnerable to rollover or lifting a tire or two. It's all about physics.

Even without an explanation one can just park a van, SUV, passenger car, and sports car side by side and intuitively tell which is most likely to lift a tire or roll in similar maneuvers.

I remember many years ago one of the TV news magazine shows like Sixty Minutes focused on the Suzuki Samurai and its propensity to roll or tip over. They were verifying test results of some testing agency. The vehicle was driven at X speed through a series of cones.

Suzuki denied the results and responded to the testers and or the news magazine. They had the chance to set the vehicle up any way they wanted. They then ran the vehicle through the same test at the same speed. The videoed their test. They then sent the unedited video to the news magazine showing the vehicle did not tip or roll over. Sixty minutes on camera showed the video to the testers for their show.

In the dealer video all though the vehicle did not tip over in the maneuver the right inside rear wheel came off the ground. The tester in watching the video for the show commented dryly and with some amazement that Suzuki would cause to be shown their vehicle lifting a wheel in reasonable turn that caused that wheel to lift off the ground.



Doctor Olds
I Need A Remedy For What's Ailing Me.
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join:2001-04-19
1970 442 W30
kudos:18
reply to neonturbo

said by neonturbo:

(youtube clip)

»www.youtube.com/watch?v=ncohOWhKaAU
Yes that is the one I could not find. Thanks!
--
What’s the point of owning a supercar if you can’t scare yourself stupid from time to time?


Darkfairy
Aeolus, your daughter flies.
Premium
join:2003-03-17
Tampa, FL
reply to Gbcue

This only proves the Grand Cherokee, while drivable on blacktop, is more setup and designed for offroad use. It is a proper SUV, designed to do what SUV's are supposed to be doing. 40 MPH abrupt turns on blacktop are not one of them.
--
Fairy Blessings,
Stefanie



Cho Baka
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join:2000-11-23
there
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reply to Gbcue

Yes, I agree. All good SUVs should roll.



I guess the BMW in the video posted earlier is also designed for offroad use.
--
The talented hawk speaks French.


neonturbo

join:2009-02-27
Lansing, MI

Any car under the wrong circumstances can roll over. You have to know the threshold of what your vehicle is capable of. A Cherokee is not meant to compete with a Porsche 911 or Corvette on the track. The test drivers in both the Jeep and the BMW videos were doing extreme maneuvers.

I have driven many Corvairs over the years, they are the ultimate "roll over deathtrap". I have never rolled even one. I have done things that should have made them roll, but yet they did not. Cloverleafs at double to triple the posted speed is white-knuckle scary (but fun!) on 175-13 tires.



Darkfairy
Aeolus, your daughter flies.
Premium
join:2003-03-17
Tampa, FL
reply to Cho Baka

A vehicle designed for offroad use is more likely to have a soft suspension with greater travel. This increases its stability and maneuverability over uneven surfaces. It also increases the force of the sudden weight transfer when doing maneuvers such as the one demonstrated.

You can roll a formula 1 car given the right circumstances. The likelyhood is just reduced by the lower weight, harder suspension and low centre of gravity.
--
Fairy Blessings,
Stefanie



Cho Baka
Premium,MVM
join:2000-11-23
there
kudos:2
reply to Cho Baka

The sarcasm wasn't obvious?



Blogger
Jedi Poster
Premium
join:2012-10-18
Reviews:
·Champion Broadba..

1 edit
reply to Darkfairy

said by Darkfairy:

You can roll a formula 1 car given the right circumstances. The likelyhood is just reduced by the lower weight, harder suspension and low centre of gravity.

True, under the right circumstances even an F1 car can flip over. But on an even surface unless it struck something it would never flip or roll no matter what. You spin the wheel while going 180 down a straightaway and the car would simply spin without leaving the ground. There are many factors that keep it from flipping with unsprung weight stiff low suspension being probably the most influential.

Beezel

join:2008-12-15
Las Vegas, NV

said by Blogger See Profile
But on an even surface unless it struck something it would never flip or roll no matter what.

You need to change that up a little "on an even surface unless it struck something it would never flip no matter what".

All it takes is the right amount of air to get under the car in a lose of control and it goes flying.