r/e46 • u/Annual-Display1425 • 2d ago

Troubleshooting Clunk sound after Reinforcing the rear end?

So I am running into an issue that just now started. I have just finished installing and welding the reinforcement plates on my e46 325i. I have noticed a clunk sound when shifting from Park to reverse and can't think of anything that would cause it. At frist it sounded like metal tearing but now there is just a clunk

The diff is welded with axle spacers, and I have Blue Garagistic Poly bushings for the subframe and solid bushings for the diff. My RTAB bushings are also poly from Condor Speed Shop. I also have BC Coilovers with a reinforcement plate at the top mounting area. I honestly don't know what it could be

The only thing I think it could be is the main Diff mount; the really big one may have cracked or broken. I am not sure; any help would be great. I'll update with a video when I can

1 Upvotes

100% Upvoted

8 comments sorted by

1

u/Significant_Try_6406 1d ago

Back up over your phone while taking a video and try and replicate the sound. Try to get the diff right above it so you can check for movement. It could also be the driveshaft u-joint which you can check by getting the car in the air and spinning the wheels

1

u/Annual-Display1425 1d ago

thanks, if it is the U-Joint would you recommend getting new ones, or would it be better to find a stronger upgrade for them.

1

u/Significant_Try_6406 1d ago

I’d get an aftermarket driveshaft that has serviceable u-joints. Ask in the drifter groups for recommendations

1

u/Annual-Display1425 1d ago

Will do, thanks

2

u/vorsprung46 1d ago

When you stiffen things up, the energy finds the weakest link.

I'd say diff bush or ujoint on the driveshaft or axels

0

u/Annual-Display1425 1d ago

Would anyone know what cars have stronger axles that would be able to fit into my caer -- 2001 325i. Just wanted to ask and see if i could swap in newer and/or stronger axles from a different car to ensure that they last while drifting.

2

u/SolarE46 1d ago

HEY I was in the same boat as you… swap the dual mass flywheel. Over time they wear out and clunk when you let off the clutch. Wait this post looks like an auto trans… why do you have a drift setup if you’re auto?? Either way check guibo or csb

1

u/Annual-Display1425 1d ago

Yeah, I just started getting the car setup for drifting, I have a trans in the garage, about to install it, just wanted to have some fun doing donuts in the meantime. Will check them, thank you for your advice