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rollover history

Posted: Thu May 13, 2004 5:22 pm
by 89b24x4project
Originally introduced by Ford Motor Company in 1983, the Bronco II was one of the most popular-selling SUVs of the 1980s with an estimated 700,000 sold in six years. The model was discontinued in 1996 in favor of more popular SUVs such as the Ford Explorer.
The Bronco II has been heavily criticized since manufacturing began for its propensity to rollover. Several lawsuits filed over the Bronco II allege the vehicle has a defective design. Ford has been accused of building the Bronco II with a center of gravity too high for the width of the track. The model's poor weight distribution allegedly makes it prone to tip over.

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The Faulty Design of the Bronco II

In 1982, Ford began production of the Bronco II, the original SUV and the precursor of the Ford Explorer. The Explorer is built on essentially the same chassis as the Bronco II, and the two vehicles have many similar characteristics. [View document].

During the development of the Bronco II, it became clear that Ford would not meet the company’s stated safety and engineering design goals. The car was too high and too narrow to "reduce rollover propensity" or "respond safely to large steering inputs which are typical of accident avoidance or emergency maneuvers." [View document].

As early as February 1981, Ford engineers identified the Bronco II’s poor stability index as a key problem with the vehicle. According to engineering documents from that time, for an additional cost of $83 per vehicle, Ford could have made a substantially safer car. [Excerpt | Full document] | [Excerpt | Full document]. These changes were rejected by Ford management, however, because they would have delayed production and sale of the vehicle. Ford did not widen the SUV three to four inches until model year 2002, almost 20 years after the engineers’ warnings.
As part of vehicle development, test vehicles are driven on test tracks through several different types of turns and maneuvers. One such turn, a J-turn test, simulates a sharp turn to test the rollover propensity of the vehicle. [View document] | [Excerpt | Full document]

Internal Ford documents show that during a 1981 test drive the fully loaded Bronco II test vehicle tipped up on to its protective outrigger or had inside front wheel lift in every J-Turn run at a mere 30 MPH. [Excerpt | Full document]. Engineers, including David Bickerstaff, who was later paid by Ford to lie about SUV safety in 30 lawsuits brought against Ford by rollover victims, recommended that Ford consider widening the Bronco II to increase the stability index—that is, make it more stable and reduce the vehicle’s propensity to roll over. [View document].

A March 17, 1982 "Bronco II Handling Evaluation" document showed that more than 9 turns resulted in lift off, and 5 turns resulted in outrigger contact, which means that the vehicle tipped on its side. [View document]. With this document, Ford engineers presented Ford management with several options to decrease the likelihood of rollovers
you can see all this info at

Posted: Thu May 13, 2004 5:27 pm
by 89b24x4project
also from 1983 to 2001 3,826 deaths of bronco II have occured in rollovers this also inclueds explorers

Posted: Thu May 13, 2004 5:52 pm
by Blue_coyote
Two very simple solutions...
1) Drive it like a 4x4 not a sports car (amazing how many morons don't know the difference!)

2) Chop the top (like the FS Bronco) Drops the CofG by a HUGE amount, and increases stability dramatically :redneck:

Posted: Thu May 13, 2004 6:04 pm
by 89b24x4project
yea i just posted that cuase i saw somethign about posting rollover history i think

Posted: Thu May 13, 2004 6:14 pm
by Blue_coyote
No sweat. I needed a legit excuse to increase my post count anyway..... :redneck:

Posted: Fri May 14, 2004 6:42 am
by plowboy
They shoulda just made it wide enough for a full size axle in my opinion. I am curious about something. Did this problem exist in the rangers, which had the same suspension or did the length extra length of the truck balance it out? Most of what I have read the problem lies with the TTB(jacking effect...the vehicle rasing up when put in a turn). Also, were there any of the same results in any of the other Ford products that had TTB suspensions...FS Bronco?

PS mine's gettin a cage...especially after I chop the top.

Posted: Fri May 14, 2004 10:08 am
by Blue_coyote
I disagree....The narrow track of the BII is an asset in the situations that it was designed for. That's what gives the Zukes a bit of an advantage. Narrow track=tighter turning radius.

Yeah, the Rangers have enough length to compensate when cornering.

No idea if it was an issue on the rest of the TTB trucks, though. The BII issue kinda overshadowed the rest.

And definitely go with a cage after a chop top. At the VERY LEAST, get a rollbar (not a show/light bar). Mind you, ANY vehicle taken offroad should have added rollover protection.

Posted: Fri May 14, 2004 11:19 am
by plowboy
It's gonna have a cage probably sooner than later like befor the top is chopped. I haven't fully comitted to chopping it yet, but the longer I look at rigs with chopped tops, the more I wish mine was. It is still and will be for a long while a daily driver as well as a weekend toy so if/when I do chop it I wan a good soft top. Oh and btw no sissy bars. Full cage only, just in case hahahaha!

Posted: Fri May 14, 2004 12:32 pm
by Blue_coyote
Yup. The only things about a chop top that require $$ are rollover bracing and the soft top. DON'T cheap out on either one (unless you're in a desert with no rain. Then the top is optional). Other than that, a chop top DD is totally do-able. More stable (measured in orders of magnitude!), lighter(by a couple of hundred pounds=better mileage as well as better cornering), and way cooler(both meanings). :redneck: <---just can't get enough of this smiley!

Posted: Fri May 14, 2004 6:47 pm
by DBrown
it always kills me to see the media pick on the BII. I enjoy my truck, even with a 3" body lift and wider rims I was completely happy with the on road performance. yes, the stock rims were a little scarry at highway speeds but with a $150 upgrade problem solved. the truth is ALL SUV's are top heavy. the them like they are SUVS. not 100mph. I think the more people become informed about what they have they will see that the problem can be corrected with little money and effort. and that is probably all the venting I would like to do because I could fill pages.............

Posted: Fri May 14, 2004 8:27 pm
by 89b24x4project
i dont see anything wrong with my stock 4x4 rims so some one please enlighten me as to why they are bad and yea i love my truck i wouldnt drive anything else exactly why i dont go 100mph evan tho it only goes 85 says the speedomeder

Posted: Fri May 14, 2004 9:20 pm
by Phillippi
I have had my B2 since I have 19ys old (1991) and drove it like a mad-kid. I have never felt like I was going over during a turn or 4x4ing. Now I have seen many cars (low cars) that have rolled due to the same j-turn trying to avoid some sort of accident or animal in the road. Its mostly driver. Of course in any vehicle if you drive with your head up your butt then you will crash. But I agree with the choptop mostly beacuse I want to chop mine really bad....

Posted: Sat May 15, 2004 12:30 am
by Blue_coyote
Phillippi wrote: But I agree with the choptop mostly beacuse I want to chop mine really bad....

1 custom soft top: Maybe $500 for something REALLY nice.
Cage or rollbar: another few hundred or so (depending on who who know and what equipment you have access to)
5" angle grinder and a few zip-cut discs: Maybe $50 if you don't already have them or their equivalent
Add maybe another $50 for whatever minor other body filler and paint you may want to cover the edges with.

Lighter, more stable, better mileage, the open sky above you.

So: the price of happiness is.....Roughly $250 to $1k, depending on how close to it you are now.

Did I mention that I base that on Canadian $?

Chop it!

Posted: Sat May 15, 2004 12:16 pm
by Phillippi
I already know I am going to do the chop, but if you have read the other post about time management then you will know that I have many other projects before the chop happens... Who knows maybe after the 5.0 I will move the chop to the top of the list and do it anyway. :laugh: