E46 Sub-frame Separation - How Common is the Problem

[Nvrgvup]

I am going to look at a 01' 330ci this weekend. I have been doing research on all the potential service, maintenance issues etc. I typically fix my own cars so most of the common issues I can take care if they come up or have been repaired by the current owner.

The one that scares me is the sub-frame tearing away form the body. I see this could cause me stress.

How common is this problem, especially with the model and year I'm looking at?? Is this a "Just a matter of Time Until it Happens to Everyone" or is it a low percentage of the total vehicles that this has affected?

I know it can be reinforced however if this is the case I'm just going to turn away from the E46's.

Thanks for your help.

[BL4CK-OUT]

It's more of an issue with the 99/00 cars. Your 01 should be fine. The problem itself isn't that common at all, I find that it's blown way out of proportion - a VERY low % of cars were affected. That said, my 01 330Ci just passed 121k miles and the subframe is perfect.

[obnoxious2]

Subframe tears are usually a result of launching the car hard with too much horsepower.

[Julian]

launching and stupid hard shifts, if you really know how to drive a manual in a non-abusive way you will be fine. the driveline shock that dropping the clutch on a launch or hard shift causes is what really kills them.

[tdz123]

Nonexistant on XI's!!!

And on rear wheel drive cars, you might be able to get BMW to fix it for free if it does happen:

http://forum.e46fanatics.com/showthread.php?t=453529

[bmwdave37]

I want to agree with the theory that hard shifts, hard launches, and high horsepower are the culprit.

The problem is, every car I've seen (maybe 4) with the problem are '99-'00 323i's with an automatic.

Talking with some fellow bmw friends, we've wondered if there is a correlation between failed rear diff mount bushings and the floor cracking.

[silentkiller]

i should know about these. mine broke in november of last year. the problem was that i had delrin bushing in the rear trailing arm and took it to the drag strip. pushed it to hard and bam. had a long crack on one of the bolts. lucky bmw covered. i said nothing about how it happend. however end up with more problems form the bodyshop as they burned my cable and made a large mess in the car. my plan is to reinforce the rear and put polyurthen bushing.

it is a 323i e46 1999 with a five speed. you should reinforce it to make sure.

[philipp122]

I want to agree with the theory that hard shifts, hard launches, and high horsepower are the culprit.

The problem is, every car I've seen (maybe 4) with the problem are '99-'00 323i's with an automatic.

Talking with some fellow bmw friends, we've wondered if there is a correlation between failed rear diff mount bushings and the floor cracking.

Who knows, you could be right. I could see poor-quality bushings causing the issue.

[MrBillyTalent]

I just found out that I need to replace my differential bushing, and have actually had to have my axle re-mounted onto the frame of my car a few thousand miles ago, (I'm at 153k) should there still be an issue with my sub-frame? If so, how do I even check it?

[Nvrgvup]

I truly love bimmers, and never had the chance to own one. Now that I am looking for a new car they are on the top of my list. However this sub-frame separation issue is really just unacceptable. I really like the E90's however there are so many nice E46's out there at good prices. This just sounds like an issue that should have been taken care of. If I buy a car like this I'm not going to beat it however I will want to drive it, sometimes aggressively. I wouldn't want to have to baby just so the rear-end doesn't rip out. This just shouldn't be an issue you have to worry about.

Is an E46 still a good car to consider or should I look at an E90 or 5-series??

[bms72586]

i love my e46...so much infact some one offered me 20,000 for mine(which i paid even less then that 1 year ago) and i turned him down. now my next big decision is a brand new 335xi or E46(2005 only with low mileage) M3 AHH decisions!

[Andolini93]

i should know about these. mine broke in november of last year. the problem was that i had delrin bushing in the rear trailing arm and took it to the drag strip. pushed it to hard and bam. had a long crack on one of the bolts. lucky bmw covered. i said nothing about how it happend. however end up with more problems form the bodyshop as they burned my cable and made a large mess in the car. my plan is to reinforce the rear and put polyurthen bushing.

it is a 323i e46 1999 with a five speed. you should reinforce it to make sure.

Bmw Repaired it for free?
Will they repair mine as well? Its a bmwe46 330ci convertible 2001 if u dont know how can i find out?

[drewusmaximus]

The 2000 and earlier has that issue. 2001 BMW used stronger metal but, they do have a patch kit for that issue.

[floydr]

Bmw Repaired it for free?
Will they repair mine as well? Its a bmwe46 330ci convertible 2001 if u dont know how can i find out?

You need to read a bit more closely: you're posting in a thread that ended in 2009. There was a recall for E46 where they would inspect and repair if it needed doing that. But that recall ended about the time this thread became inactive; it's not likely that a dealership will honor the recall. And your car may have been inspected in the recall and not repaired because it didn't show the problem.

You can try by talking to a dealer, but my guess would be way to late.

[dhurley34]

Convertibles virtually had zero subframe issues because the sheet metal is thicker on conv.'s for strength throughout the entire production run.