Preventing Subframe cracks

[Vic Romano]

Im a newb and am looking at getting an M Coupe until I found out about the subframe issue. Now Im sorta hesitant and am leaning towards my second choice which is an E36 M3. I did a search and read some of the past posts but I still had some questions.

1) Do ALL MC's end up with subframe issues (cracks, rips, separations)?
2) Are certain years more prone to the subframe issue. Would a 99 have more of a chance to develop these problems than a 2000??
3) to prevent this from happening. Can I drill out the old spot welds and re-weld that area?
4) are there anyways to prevent the differential mount from tearing or is there a way to beef it up?
5) I've seen that many people wanted to take action at BMWNA by writing/calling/petitioning, has BMW responded in any way?

Thanks for any more insight about this topic. I really want to get an MC but I cant have this crap happening to a $20K+ used car.

Mike

[rayray]

its inevitable........MUAHAHAHAHAHAHHAHA the subframe crack will own you MUAHAHHAHAHAHA...j/k...bump for the coupe guys.. #3 will solve your subframe problems along with custom extra reinforcement.(preventive maintenance).

[tripleM]

Vic, here are some quick answers & a definitive link to your questions:
http://www.thelargeglass.com/bmw/subframe/
1) No
2) Anecdotal evidence suggest S52 cars but general answer NO
3) Several solution available with 1 in NJ costing ~$800
4) YES
5) Case by case basis (but mostly favorable as good will gesture)

You've come to the right place.
The car is bulletproof saved for this issue & can be remedied easily & with lotsa support from community!

Good luck in your search!

Im a newb and am looking at getting an M Coupe until I found out about the subframe issue. Now Im sorta hesitant and am leaning towards my second choice which is an E36 M3. I did a search and read some of the past posts but I still had some questions.

1) Do ALL MC's end up with subframe issues (cracks, rips, separations)?
2) Are certain years more prone to the subframe issue. Would a 99 have more of a chance to develop these problems than a 2000??
3) to prevent this from happening. Can I drill out the old spot welds and re-weld that area?
4) are there anyways to prevent the differential mount from tearing or is there a way to beef it up?
5) I've seen that many people wanted to take action at BMWNA by writing/calling/petitioning, has BMW responded in any way?

Thanks for any more insight about this topic. I really want to get an MC but I cant have this crap happening to a $20K+ used car.

Mike

[count_schemula]

I have a 7/98 build with 61k miles... no problems.

[BETO]

This happens to ///M Roadsters as well, right?

[count_schemula]

Im a newb

It's no0b.

[6i9]

Vic, here are some quick answers & a definitive link to your questions:
http://www.thelargeglass.com/bmw/subframe/
1) No
2) Anecdotal evidence suggest S52 cars but general answer NO
3) Several solution available with 1 in NJ costing ~$800
4) YES
5) Case by case basis (but mostly favorable as good will gesture)

You've come to the right place.
The car is bulletproof saved for this issue & can be remedied easily & with lotsa support from community!

Good luck in your search!

What's the fix in New Jersey? Links? Threads?

[tripleM]

What's the fix in New Jersey? Links? Threads?

http://bimmer.roadfly.org/bmw/forums...5538804-1.html
http://www.bimmerfest.com/forums/showthread.php?t=67281

[Vic Romano]

http://www.bimmerfest.com/forums/showthread.php?t=67281

So are there any close up pics or more descriptions about what they're actually doing?? I've seen a couple pictures of various weld jobs but I cant really make it out since I haven't been underneath an MC.

5) Case by case basis (but mostly favorable as good will gesture)

So, Im assuming BMWNA will only deal with this if you are under warrenty. correct??

[Randy Forbes]

So are there any close up pics or more descriptions about what they're actually doing?? I've seen a couple pictures of various weld jobs but I cant really make it out since I haven't been underneath an MC.



So, Im assuming BMWNA will only deal with this if you are under warrenty. correct??

You must've missed the threads on my black car (well documented that it was out of warranty by a couple years). The entire story is in the link you were given.

Here are links directy to picture documentation.

http://www.rfdm.com/Randy/BMW/pics/p...99-TrunkFloor/

http://www.rfdm.com/Randy/BMW/pics/p...Reinforcement/

Edit: it should be pointed out that these repairs are of my own design; implementation was done by my BMW dealer and covered under warranty by BMWNA. The 99 has the original differential bracket doubled up (two brkts sandwiched together) and the 01 has the E-36 M3 dual mounting ear differential cover fitted (it has since been replaced with the Rogue version). Do not expect to walk into your local dealer and have them offer you either of these repairs as the standard fix.

[tripleM]

Edit: it should be pointed out that these repairs are of my own design; implementation was done by my BMW dealer and covered under warranty by BMWNA. The 99 has the original differential bracket doubled up (two brkts sandwiched together) and the 01 has the E-36 M3 dual mounting ear differential cover fitted (it has since been replaced with the Rogue version). Do not expect to walk into your local dealer and have them offer you either of these repairs as the standard fix.

Randy, is your repair covered under any BMW warranty? By that I mean, if something goes bad with the fix, that they will repair again (not that I think your engineering will fail in a mm yrs! )

[tripleM]

So are there any close up pics or more descriptions about what they're actually doing?? I've seen a couple pictures of various weld jobs but I cant really make it out since I haven't been underneath an MC.??

http://bimmer.roadfly.org/bmw/forums...5137630-1.html

So, Im assuming BMWNA will only deal with this if you are under warrenty. correct??

Case by case even if you are out of warranty like Randy said above. They call it a good will gesture after warranty.

One thing to remember is that a lot of this reengineering, including the BMW's fix, is highly unproven. We won't know until several years down the road if some if any work @ all. But I'd put my uninformed money on some of the highly thoughtout solutions rather than just rewelding.

[rlcanon]

On the topic of preventing subframe cracks, it's my opinion that the Ireland Engineering poly subframe bushings will go a long way in that direction by keeping the subframe from wallowing around and stressing the diff mount/subfloor. That and the vast improvement in handling with no appreciable down-side (other than pulling the stock bushings) make them a win-win!

[Greg]

My M coupe was a 99, and it had a SC, so I was running at least 310 to the wheels. My subframe tore like rice paper! Granted with the supercharger, the car did hole shots like a king!
In the same token a friend had an 00 car with even more power never had the slightest issue.. He made a peak of 419 TO THE WHEELS, and his subframe was fine with whole shots from every traffic light!!

The deal is, I believe in 00 they beefed the sheet metal up, and revised the design... If you compare the ear that holds the bottom portion of the dif from a 99 car to an 00 car, you'll notice that the piece has a lip to it, adding reinforcement.

BTW, this is the second time one of my BMWs suffered a subframe failure.
The cause of this... Cost Accountants, who are always looking to cut corners in costs... Also, these cars, unlike the early ones, are results of CAD design, and are tested via computer simulation...
The older M cars were built by hand, and never suffered this issue..
This is referred to as Marginal Engineering.. Essentially saying just enough to get by...
What I've notice owning a Porsche is that a 1990 car can handle over double it's horsepower, and not fail. THAT IS IMPRESSIVE. That's why they are so expensive too.

[leland 50]

If I am not mistaken, Dinan makes a reinforcement kit for about $500. It says that it requires significant dissassemblyof the car for instalation.

[B R]

2 things 2 think about. If you don't drive the car, it should not have any problems . Don't think that E36s are immune from problems, they aren't .

[TitanMZ3]

Does anyone know what gauge steel was used in Randy's trunk floor reinforcement pieces?

[6i9]

So can anyone explain to me what the fix in New jersey is specifically? Do they just reseal your welds and make it "stronger" in doing so? (how does that work?)

The subframe problem is the biggest fear I have to learn how to track this car.

[Randy Forbes]

Does anyone know what gauge steel was used in Randy's trunk floor reinforcement pieces?

Randy does...

Ten gauge (10Ga.) mild steel used throughout. Might be possible to use 12 or 14 Ga., but I used 10Ga.

[Randy Forbes]

So can anyone explain to me what the fix in New jersey is specifically? Do they just reseal your welds and make it "stronger" in doing so? (how does that work?)

The subframe problem is the biggest fear I have to learn how to track this car.

I guess only a few people really know (sworn to secrecy?). If the guy is that worried about people copying it, it must be pretty simple.

As I envision it, it consists of a piece of 1" square tubing across the width and behind the existing xmbr with flat (horizontal) gussets to the longitudinal rails. With additional bracing to the rear face of the existing differential bracket. All this is done below the trunkfloor.

Only cost you $700-$800 to know for sure

[6i9]

I guess only a few people really know (sworn to secrecy?). If the guy is that worried about people copying it, it must be pretty simple.

As I envision it, it consists of a piece of 1" square tubing across the width and behind the existing xmbr with flat (horizontal) gussets to the longitudinal rails. With additional bracing to the rear face of the existing differential bracket. All this is done below the trunkfloor.

Only cost you $700-$800 to know for sure

That's true, but for $800, I want to at least know what's gonna be done onto my car. I can't be expected to blindly hand my car over (even though technically I would be, because I don't understand welding/frame jobs too well)

[Randy Forbes]

Randy, is your repair covered under any BMW warranty? By that I mean, if something goes bad with the fix, that they will repair again (not that I think your engineering will fail in a mm yrs! )

Good question, I hope I never have to find out! By rights, any repair under warranty is covered for one year.

Say they replace your transmission on the last day of your manufacturer's warranty (bumper to bumper, 4yr/50,000mi or whatever you want to call it). That transmission (and the labor required to install another one) is covered for one additional year. That is the explanation I was given about one of my replacement tops (replaced after the warranty had expired but still less than a year since the previous replacement top).

But hey, thanks for the endorsement

[Randy Forbes]

That's true, but for $800, I want to at least know what's gonna be done onto my car. I can't be expected to blindly hand my car over (even though technically I would be, because I don't understand welding/frame jobs too well)

Well, if it makes you feel any better, the work I did on my gray car (dual ear) would cost you nearly three times (3X) that. If I did it, that is

[Randy Forbes]

On the topic of preventing subframe cracks, it's my opinion that the Ireland Engineering poly subframe bushings will go a long way in that direction by keeping the subframe from wallowing around and stressing the diff mount/subfloor. That and the vast improvement in handling with no appreciable down-side (other than pulling the stock bushings) make them a win-win!

While I agree 100%, I am careful to add that I do not believe the IE bushings are enough (by themselves) to eliminate the threat.

But they are without a doubt, the best $90.00 you can spend on your car! And it should be everybody's 1st suspension mod.

[Vic Romano]

You must've missed the threads on my black car (well documented that it was out of warranty by a couple years). The entire story is in the link you were given.

Here are links directy to picture documentation.

http://www.rfdm.com/Randy/BMW/pics/p...99-TrunkFloor/

http://www.rfdm.com/Randy/BMW/pics/p...Reinforcement/

Dang, thats pretty extensive. I dont know if I have the guts to do that to my car. I wouldnt want to screw up the suspention geometry, crumple zones, etc.. Great job Randy!