Replacing Trailing Arm Bushings on Project BMW E46

That sounds complicated.

You’re damn right it is. But now that you’ve read that, you understand that a multi-axis bushing has some serious engineering brain power behind its design.

A polyurethane bushing is meant to be rigid, and will bind during that multi-axis movement. This results in somewhat snappy handling as the force of the wheel moving, and suspension compressing and rebounding powers through the resistance of the bushing. Polyurethane is not recommended for BMW rear trailing arms because of this. Many BMW race shops will tell you the same.

A quick visual inspection shows that the RTABs on my E46 are shot. These stock rubber bushings allow for the proper multi-axis suspension movement. The trade-off is that, eventually, the rubber fatigues from the constant movement, and tears. If left alone and untended for long enough, the bushing can tear all the way through. Then the trailing arm falls out of the car and everyone has a bad time.

So, this all leads me into the solution: Hardened rubber bushings.

A tougher rubber bushing will still allow for that primo multi-axis movement we’re after, but better hold up to the abuse of drifting. To that end, I sourced Meyle HD bushings, which utilize a stiffer durometer rubber. But that’s not all. Even with these stiffer bushings, it’s possible for the trailing arm to go too far in its movement. This leads to sloppy handling, and, you guessed it, increased bushing fatigue. To that end, the aftermarket has developed trailing arm bushing limiters. These solid pieces of polyurethane, delrin, or metal slot in between either end of the bushing, and the bushing mount and physical limit the bushing movement to a normal range, prohibiting excessive movement, or deflection. Perfect!

Continue onto the next page to keep reading.

Jake Stumph

Jake Stumph is a lifelong car enthusiast and racer, and former content editor for Internet Brands Automotive which he joined in 2015. His work has been featured by several other prominent automotive outlets, including Jalopnik and Autobytel.

He obtained a bachelor's degree in Political Science at the Ohio State University in 2013, then pivoted from covering politics and policy to writing about his automotive adventures, something that, he says, is a lot more fun. Since that time, he has established connections with most of the world's major automakers, as well as other key brands in the automotive industry.

He enjoys track days, drifting, and autocross, at least, when his cars are running right, which is uncommon.

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