Member
Hey everyone ive had a clunk problem for a long while now , originally i found my diff front bolt was snapped as ive read it happens commonly. fast forward i swapped everything poly and put new hardware in. car sat for a long time due to some issues i couldn't get to. now im back at fixing it and i and trying to figure out why the clunk is still there . i have a video attache just to get everyone opinions on what is happening. major things i noticed when i looked under today were that it i couldnt see any tearing of the sub frame and they are reinforced but the back most 2 subframe bushing do seem like that have a 1/4 finger top size gap from the underside of the car . also the sub frame bushing are aswell poly.
idk how to attach a video or if you even can because it would work so i downloaded to youtube...
youtube link : https://youtu.be/7sgs_xGfPu4
Member
Something is not bolted up properly... My guess is you did something wrong with the subframe mounting? Common noise problems are rtabs and upper strut mounts, check and make sure those are good, then unbolt the subframe and figure out what you did wrong in a hurry.Originally Posted by Iamjustin23!
#buttstuff2k14
BMW CCA Member
Make sure those bushings are installed correctly. They may have an orientation that you didn't get right, as the bushings are supposed to sit flush to the body of the car.
Member
Is it me or is the entire floor above the rear of the subframe flexing!!!!!!!!!
I was expecting to see the subframe bolts/subs ripped but i see the whole floor moving.
Member
The floor can flex and crack. It is only spot welded. Chikinhed has a thread on this in the FI subforum. His car is big power and tracked on sticky rubber so more stress than most. He detailed his repair and reinforcement as well.
Member
yes i noticed the floor moving as well i though maybe it was just the seating of the car as i pressed the throttle. i can look for his thread to see what he did . im also trying to find the bolt size of the subframe if anyone knows off hand because ecs and realoem website have contradicting answers and i messeged ecs and they have said nothing to me.
Member
M12x1.5 is it, I think. Look up the bolts on realoem.
Member
got the bolts yesterday tightened them down , seems like it helped a tiny bit but the clunk is still there . gonna check to see if anything else is loose today. hopefully can get this sorted out. does anyone know what other bolts could cause that type of movement mostly on the backside of the diff? in the video it seems the back end moves alot more then the front bolt of the diff?
Member
2 bolts in the front, 2 in the rear. While the video is not the best, your floor looks like it's buckling. If you have a fold down back seat, fold it, remove the trunk carpet and insulation and video it while driving.
Posting Permissions
Reply With Quote
Bookmarks