E36 Safety and IT

[JoshS]

Bingo.

They idea that that manufacturer's designs are structurally lacking is amusing.

Well, to be fair, there are REAL issues. BMW very recently settled a class-action suit with E46 owners because the unibody fails where the rear subframe mounts, and there is now factory guidance on how to reinforce the unibody at those locations (it involves using structural foam.) Exactly the same sort of structural failure happens on both the E36 and Z3 chassis too, although unfortunately they aren't included in the settlement. It's as though BMW engineers just don't know how to build a chassis that can hold a rear subframe without breaking apart. These failures are relatively common on street cars.

Likewise, the front control arm failures are well-documented -- they have embedded ball joints for the inner pivot and these fail regularly. Racing guidance suggests replacing them every season or two. Likewise there are weaknesses that have shown themselves on racing cars again and again with E36 front subframes, E30/Z3 rear trailing arms, etc.

I'm not lobbying for any sort of rule change. We live with these things and lots of manufacturers have these sorts of struggles. I'm just pointing out that it's not as though these are all performance issues masquerading as safety issues. In a lot of ways, many street cars, especially once they get up there in miles, are not up to the task of racing, or in some cases, even driving around on potholed streets.

[dj10]

If it ani't broke don't fix it.

[Duc]

Isn't there a TSB for the changes?

[JeffYoung]

True not just of BMWs.

In a lot of ways, many street cars, especially once they get up there in miles, are not up to the task of racing, or in some cases, even driving around on potholed streets.

[Xian]

Lot's of cars need parts replaced annually. CRX/Civic's should have the hubs/bearings replaced annually and even the front uprights can be prone to failure.

[europeanspec]

The "modifications" he is talking about is to keep the sub-frame, shock towers and strut towers from tearing out of the car. I guess you could wait until they fail, but that is ridiculous. With the M3, BMW fixed the problem. The repair pieces are available through BMW. They don't provide any advantage other than being able to keep the tub from coming apart.

Are you allowed to fix a chassis or do you have to throw it out when something happens to it?

[lateapex911]

So the whole thing just rips out and ends up at teh side of the road at once!?

[Xian]

You can fix the chassis in accordance with factory repair methods. FWIW, many Honda products have problems with the rear subframe tearing out too... we just inspect it regularly and fix it when it happens.

[Ron Earp]

It seems that about every twelve months the E36 subframe debate pops up.

[Doc Bro]

So the whole thing just rips out and ends up at teh side of the road at once!?

Kinda...

Last year at NHMS Dave hit some Oil Dry in Nascar 1&2 in his e36, and lost traction, then regained traction with a quick slide ocurring. On corner exit he knew something had happened beyond the loss of grip. He immediately pulled the car in. Dan immediately checked the subframe mounts and noticed a crack. Loaded the car and called it a weekend. When Dan put the car on the lift he noticed it had ALL cracked, including breaking the trans mounts and the motor mounts....literally ripped the driveline out of the car. Took him a week to fix......how's that for a failure from Oil Dry?

R

[Greg Amy]

...how's that for a failure from Oil Dry?

I HIGHLY doubt all that damaged was caused in that one moment; the amount of stress needed to rip sheet metal to that magnitude in one instant is absurdly immense, far more than even the vaulted awesomeness of a BMW can generate (even without the SIR ). I'm much more likely to believe that this damage had been propagating for quite some time, with a small crack fatiguing and growing to the point where a minor incident as you describe finally allowed it to break across a critical area.

Sounds more like lack of adequate on-going inspection of a critical safety area, to me.

GA

[gsbaker]

Well, to be fair, there are REAL issues. BMW very recently settled a class-action suit with E46 owners because the unibody fails where the rear subframe mounts, and there is now factory guidance on how to reinforce the unibody at those locations (it involves using structural foam.) Exactly the same sort of structural failure happens on both the E36 and Z3 chassis too, although unfortunately they aren't included in the settlement. It's as though BMW engineers just don't know how to build a chassis that can hold a rear subframe without breaking apart. These failures are relatively common on street cars.

Likewise, the front control arm failures are well-documented -- they have embedded ball joints for the inner pivot and these fail regularly. Racing guidance suggests replacing them every season or two. Likewise there are weaknesses that have shown themselves on racing cars again and again with E36 front subframes, E30/Z3 rear trailing arms, etc.

I'm not lobbying for any sort of rule change. We live with these things and lots of manufacturers have these sorts of struggles. I'm just pointing out that it's not as though these are all performance issues masquerading as safety issues. In a lot of ways, many street cars, especially once they get up there in miles, are not up to the task of racing, or in some cases, even driving around on potholed streets.

I wasn't aware of that. Thanks for the education.