i installed spohn LCAs and now i have gear noise from the rear end and at certain RPMs , a driveline vibration, only for a bit. these shouldnt have changed anything, why is it doing this? im getting the relocation brackets welded on in a few days. im just wondering if anyone else has had this or knows why?

 

Sounds like the pinion angle is off. Are the RCAs the adjustable type??

 

sounds like you got poly bushings , and they are harder so you will get a little more sound from everything.

 

yea theyre poly bushings, but they shouldnt be making this kind of noise. no they are not the adjustable ones. there was a bit of noise from the carrier before, i hadnt gotten a chance to get it back in the shop to get it adjusted before i put these on. but this is a night/day difference in the loudness of the gear noise. and the driveline vibration was never there before. it just seems odd that it would cause this much noise.

 

If their non-adj then they shouldn't have changed any geometry from the original set-up. Just to be sure, all you changed at the time was the LCAs - right? Only asking because if you did some other work, maybe the problem is elsewhere.

And I guess I would add don't under estimate too much just how much drivetrain noise the poly/poly LCAs can transmit to the chassis. If I understand correctly, you said your rear axle was making some abnormal sound already; if that was/is the case, the poly/poly LCAs might be amplifying that abnormal sound quite a bit. The d@mn things are really hard and very unforgiving, especially when brand new, so they might be the culprit. If no geometry changed, could just be the LCAs. Just my two cents though.

K

 

well im gonna get the rear end reshimmed.... for the third time and then see how the noises are. i swear, if i have to bring it in for this again, im gonna go postal on that place. and the worst part is, i used to work there. i havent ever had anything w/ poly bushings before so it could just be that im not used to any of it. thanks for the input guys.

 

agreed. you will have more noise from poly. im sure thats not the total cause but its a contributer