So what started as a small job replacing all the control arms has become a fully fledged rear end rebuild.
I started out with a pile of M3 controls arms, the 4 up front and 6 in the rear (only 4 of them are the M3 ones, the rear arms are the 335i ones) along with some new trailing arms. I has also decided to rebuild all the calipers while I had the wheels off and also wanted to refresh all 6 brake lines. But upon inspection of the rear subframe I could see the diff leaking at the pinion seal and the brake lines were welded together since I live in an area that spreads salt in winter.
So after pulling all the control arms off the car I decided the proper way to proceed would be to drop the rear subframe so I could replace the hard brake lines that run along the top of the subframe and the 2 flex lines that are hidden away. I also need to fix the leaking diff so it seems like the common sense thing to do.
So while I'm in there I thought it would be a good time to replace the subframe bushings.
So my 2 questions:
1. Is it feasible to DIY the leaking diff? I've looked at a few threads and the BMW TIS info and I'll be honest, it looks a little painful. Part of me just wants to buy an LSD and just swap it over. (I don't actually want or need an LSD, this car will never see a track). Does anyone have experiences with leaky diffs?
2. Subframe bushings look like a PITA. I was planning on M3 bushings but the forums say that I should use Condor Speed UHMW bushings as they are better and also much easier to install. The internet says there's no downsides to these stiffer bushings, is this the right way forward for someone who isn't a racecar driver?
I'm going to be buying a load of parts and attempting to get this done over a long weekend, so any tips on useful tools or parts to change while in there would be much appreciated.
I started out with a pile of M3 controls arms, the 4 up front and 6 in the rear (only 4 of them are the M3 ones, the rear arms are the 335i ones) along with some new trailing arms. I has also decided to rebuild all the calipers while I had the wheels off and also wanted to refresh all 6 brake lines. But upon inspection of the rear subframe I could see the diff leaking at the pinion seal and the brake lines were welded together since I live in an area that spreads salt in winter.
So after pulling all the control arms off the car I decided the proper way to proceed would be to drop the rear subframe so I could replace the hard brake lines that run along the top of the subframe and the 2 flex lines that are hidden away. I also need to fix the leaking diff so it seems like the common sense thing to do.
So while I'm in there I thought it would be a good time to replace the subframe bushings.
So my 2 questions:
1. Is it feasible to DIY the leaking diff? I've looked at a few threads and the BMW TIS info and I'll be honest, it looks a little painful. Part of me just wants to buy an LSD and just swap it over. (I don't actually want or need an LSD, this car will never see a track). Does anyone have experiences with leaky diffs?
2. Subframe bushings look like a PITA. I was planning on M3 bushings but the forums say that I should use Condor Speed UHMW bushings as they are better and also much easier to install. The internet says there's no downsides to these stiffer bushings, is this the right way forward for someone who isn't a racecar driver?
I'm going to be buying a load of parts and attempting to get this done over a long weekend, so any tips on useful tools or parts to change while in there would be much appreciated.
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