The definitive subframe strategy thread

[KwaK]

Re-doing mine now. Pics to come soon. I have yet to really enjoy this car!

[Gofast]

Do you find it makes the car go faster, since you're no longer worried about it?

I will say, I heard people say it made the car feel much more solid and planted, and I thought it was an exaggeration.
Having installed the kit, it's definitely true. The whole car feels much more together and predictable in transition; and this is in a gutted car that already had a 6-point welded in half cage.

[Randy Forbes]

I will say, I heard people say it made the car feel much more solid and planted, and I thought it was an exaggeration.
Having installed the kit, it's definitely true. The whole car feels much more together and predictable in transition; and this is in a gutted car that already had a 6-point welded in half cage.

Wow, thanks for posting that!!

[M Roadster]

So...my car just went out for repair. I can't wait to get her back. In the mean time, I made a little teaser. Take a gander.

http://www.youtube.com/watch?v=ksIjU...ature=youtu.be

[Reddy Kilowatt]

While I had my trunk torn apart, I snapped photos. It doesn't seem like any symptoms of pending failure are present, but I'd be interested in opinions from the group here. Click on the thumbnails for larger photos. Thanks!

[Randy Forbes]

As you know, it's harder to detect the onset of problems in a Coupe, because of the asphalt mat, but "I" don't see any obvious signs of trouble.

[Reddy Kilowatt]

As you know, it's harder to detect the onset of problems in a Coupe, because of the asphalt mat, but "I" don't see any obvious signs of trouble.

Thanks Randy. I still intend to do preventive install of one of your kits, but if I don't need to do it right now, I might punt until next winter. I'll send you an email with information about a potential local installer to see if you think they're a good candidate to do the work.

Cheers!

[cfmistry]

As you know, it's harder to detect the onset of problems in a Coupe, because of the asphalt mat, but "I" don't see any obvious signs of trouble.

Hi Randy Forbes,

I was wondering if you (or anyone else!) could take a look at my pictures and tell me if my subframe is ok.

The trunk floor isn't warped the way some bad cases I've seen are, but the spot welds look a little sunken in the middle and worry me. Hopefully I'm worrying over nothing.

Thanks,
Cyrus

[Reddy Kilowatt]

Cliff Notes!

This thread is quite long, and many of the photos and links from the early days are broken. The thread is still worth reading in its entirety, but for those who just need to get down to brass tacks, I'm hoping this distillation is helpful. If I've missed any critical information, point it out to me and I can edit it into this post.

Steps to access trunk floor
http://forums.bimmerforums.com/forum...&postcount=263

Diagnosis photos
http://forums.bimmerforums.com/forum...&postcount=181

Pictures of asphalt mat removal and re-install
http://forums.bimmerforums.com/forum...&postcount=755

Single-ear reinforcement
http://forums.bimmerforums.com/forum...&postcount=846

Repair photos & bushing recommendation
http://forums.bimmerforums.com/forum...&postcount=185

Link w/ pictures of cars post-repair
http://forums.bimmerforums.com/forum...&postcount=790

More repair photos
http://www.spcarsplus.com/gallery3/i...time-s-a-charm

California installation
http://forums.bimmerforums.com/forum...&postcount=778

[M Roadster]

I just got my car back an hour ago. Holy moly! What a difference! I never knew how loose everything got prior to the fix. Everything's very tight now. It drives better than I remember it (I also got a strut tower bar). The added bonus for me is the diff whine I hear as I accelerate. It's great. PerformanceTechnic and RandyForbes, thank you so much for everything.

[chgrec]

[QUOTE=cfmistry;25838612]Hi Randy Forbes,

I was wondering if you (or anyone else!) could take a look at my pictures and tell me if my subframe is ok.

The trunk floor isn't warped the way some bad cases I've seen are, but the spot welds look a little sunken in the middle and worry me. Hopefully I'm worrying over nothing.

Thanks,
Cyrus
[QUOTE=cfmistry;25838612]

It actually looks like it is just beginning to me...See the rust on the inner left edge of the weld spot? that rust seems like the metal is just starting to separate the paint, which allowed oxygen to get to the metal below and rust....Just my opinion.

Chris

[Gofast]

The added bonus for me is the diff whine I hear as I accelerate. It's great. PerformanceTechnic and RandyForbes, thank you so much for everything.

I did notice that too, I think the metal/metal contact of the e36 cover combined with the stiffness of the Forbes kit transmits more diff noise into the cabin.
Of course, it's not helping that I have no interior or sound deadening.

It actually looks like it is just beginning to me...See the rust on the inner left edge of the weld spot? that rust seems like the metal is just starting to separate the paint, which allowed oxygen to get to the metal below and rust....Just my opinion.
Chris

Agreed, that's the very start of it.

[cfmistry]

It actually looks like it is just beginning to me...See the rust on the inner left edge of the weld spot? that rust seems like the metal is just starting to separate the paint, which allowed oxygen to get to the metal below and rust....Just my opinion.

Chris

Agreed, that's the very start of it.

Well, thanks (?) for the bad news guys. I appreciate you taking the time to help! I can't afford to drop $2500 on the car right now, so if I drive her gently do you think everything will hold up until I can get the RF kit?

Thanks,
Cyrus

[chgrec]

Well, thanks (?) for the bad news guys. I appreciate you taking the time to help! I can't afford to drop $2500 on the car right now, so if I drive her gently do you think everything will hold up until I can get the RF kit?

Thanks,
Cyrus

Sorry for the bad news. Having had my own M fall to this issue, I know exactly how it feels. The trunk floor welds are only part of the potential failure points. You need to get up under the car and check it out, especially the diff tab for tears where it bends around the cross member. I did a temporary drilled hole & bolt fix while I saved up the money for Randy's ket. It held for 2 years before the diff tab itself ripped off and my diff fell down. Fortunately I was only pulling out of a parking lot and not cruising at highway speeds.

So yes, you can do some temp stuff to get by but ultimately it will fail unless you get it fixed right. and by right I mean Randy’s fix....Which I have had on for 3 years without a bit of trouble even though I installed it myself…


(my rear issues can be seen here: http://www.flickr.com/photos/chrisgr...7601453916512/ )

Chris

[Gofast]

Well, thanks (?) for the bad news guys. I appreciate you taking the time to help! I can't afford to drop $2500 on the car right now, so if I drive her gently do you think everything will hold up until I can get the RF kit?

Thanks,
Cyrus

Absolutely, I drove and autoX'd regularly for over a year with worse damage than that. You're nowhere near the point of an emergency.
Just keep an eye on it, and try to drive relatively gently most of the time. You can easily get several years out of the car if you pay attention and treat it carefully.

[tttoon]

I just got my car back from Randy, and I couldn't be happier with the work. I'm in AZ, but since there was no local installer, I decided to ship the car to FL. I could've had it done in the Bay area, but in the end that would not even have saved me much money. I worked with Randy's usual trucking broker and paid $850 and $750 respectively. Total time I did not have the car was 6 weeks. Following the work is amazing, and you can tell there is nobody who a) knows more about these cars and b) pays attention to the details like that.

I haven't driven the car much yet, and I have a 500 mile break in for the new rod bearings ahead. But overall I'm a very happy man tonight.

[Jeremy]

I just got my car back from Randy, and I couldn't be happier with the work. I'm in AZ, but since there was no local installer, I decided to ship the car to FL. I could've had it done in the Bay area, but in the end that would not even have saved me much money. I worked with Randy's usual trucking broker and paid $850 and $750 respectively. Total time I did not have the car was 6 weeks. Following the work is amazing, and you can tell there is nobody who a) knows more about these cars and b) pays attention to the details like that.

I haven't driven the car much yet, and I have a 500 mile break in for the new rod bearings ahead. But overall I'm a very happy man tonight.

Congrats! Randy replaced my conrod bearings as well when my Coupe was on its way from PA to AZ 3 years ago. Good to see another PHX M Coupe! Nearly all the Coupe owners that I knew from around here sold theirs or moved out of state. I'm in NW Peoria, not far from Lake Pleasant.

[Randy Forbes]

I just got my car back from Randy, and I couldn't be happier with the work. I'm in AZ, but since there was no local installer, I decided to ship the car to FL. I could've had it done in the Bay area, but in the end that would not even have saved me much money. I worked with Randy's usual trucking broker and paid $850 and $750 respectively. Total time I did not have the car was 6 weeks. Following the work is amazing, and you can tell there is nobody who a) knows more about these cars and b) pays attention to the details like that.

I haven't driven the car much yet, and I have a 500 mile break in for the new rod bearings ahead. But overall I'm a very happy man tonight.

Thank you Toon! The 500 miles is more of a suggestion than a mandate, just be sensible

Yes, sorry about the six (6) Coupe-less weeks. I think I had it three (3) weeks before I was able to work on it...

[Mr Bingley]

I just got my car back from Randy, and I couldn't be happier with the work. I'm in AZ, but since there was no local installer, I decided to ship the car to FL. I could've had it done in the Bay area, but in the end that would not even have saved me much money. I worked with Randy's usual trucking broker and paid $850 and $750 respectively. Total time I did not have the car was 6 weeks. Following the work is amazing, and you can tell there is nobody who a) knows more about these cars and b) pays attention to the details like that.

I haven't driven the car much yet, and I have a 500 mile break in for the new rod bearings ahead. But overall I'm a very happy man tonight.

I got mine back from him a little over a year ago--just before he moved to Florida--I am so glad I had him do it--man that's quality. That was very smart of you to ship it instead of trying to find a local installer--well worth the additional cost--congrats.

[Kornknarr]

Today I finished the installation of the exhaust and with that my whole subframe/crossmember/RF-kit/bushing job is completed. If anyone want to see the whole process you can do it here:http://perkornhall.se/Per_Kornhall/Subframe.html
Not all of the texts are in English but most.



Per

[dcrothers]

Nice job and congrats.. It's on my todo list....
Anyone that can recommend a welder that's cheaper than the Millermatic?

[Gofast]

Nice job and congrats.. It's on my todo list....
Anyone that can recommend a welder that's cheaper than the Millermatic?

I would stick with a Miller or similar name-brand welder (the Hobart Handler looks pretty good). I've found that a low-power MIG is one place you don't want to cheap out.
I did mine with a Millermatic 140 with good results, nice steady power and no tripped breakers. A lower-quality off brand MIG will have difficulty holding a steady current on a 120V house circuit, and your work may suffer.
It's ultimately up to you, but I'd find somewhere else to cut $200, your welder can make or break the project.

[Z3MRacer]

I'm sure this info is out there somewhere, but I recently had my BMW search this part out for me.
I picked up the OEM replacement diff ear today. The P/N is 41 11 8 398 664 and cost me $21.75.

[Mr Bingley]

I'm sure this info is out there somewhere, but I recently had my BMW search this part out for me.
I picked up the OEM replacement diff ear today. The P/N is 41 11 8 398 664 and cost me $21.75.

Ok, you need to read this thread--either that or we need a new definitive subframe strategy thread that is easier to plow through--clearly we are not imparting the information we need to. Too many people are not getting what they need to properly understand the subframe/trunk floor/diff mount issue, and the solutions available. 36 pages of material is simply too much for a noob to process before they buy their car. This thread only needs to be one post, or, at most, one page--it needs to be clear, precise, to the point, and definitive. We have done a disservice to the community by letting it go this long. The subframe/trunk floor/diff mount issue is a big deal and people need to be clearly warned and apprised of the options and potential costs associated with those options.

Ok, rant over--I've just written too many responses lately to questions that could have been asked and answered before purchase.

[Reddy Kilowatt]

^ This was intended to do just that, though perhaps it's missing basic and detailed descriptions of the problem.

Cliff Notes!

This thread is quite long, and many of the photos and links from the early days are broken. The thread is still worth reading in its entirety, but for those who just need to get down to brass tacks, I'm hoping this distillation is helpful. If I've missed any critical information, point it out to me and I can edit it into this post.

Steps to access trunk floor
http://forums.bimmerforums.com/forum...&postcount=263

Diagnosis photos
http://forums.bimmerforums.com/forum...&postcount=181

Pictures of asphalt mat removal and re-install
http://forums.bimmerforums.com/forum...&postcount=755

Single-ear reinforcement
http://forums.bimmerforums.com/forum...&postcount=846

Repair photos & bushing recommendation
http://forums.bimmerforums.com/forum...&postcount=185

Link w/ pictures of cars post-repair
http://forums.bimmerforums.com/forum...&postcount=790

More repair photos
http://www.spcarsplus.com/gallery3/i...time-s-a-charm

California installation
http://forums.bimmerforums.com/forum...&postcount=778