22kart22

Hey guys and gals, Since December my car has been making a really loud rear chirping noise upon deacceleration and coasting in any gear-including neutral. It all began with a few runs down the 1/8th mile.

I took the car to CrazyHorse Racing and Chris and I took it for a drive and he commented on how odd of a sound it makes and how loud also. We put it on the lift and decided the issue is a bad cv joint in the driveshaft or a pinion bearing going bad slowly. He said he has heard many bad gear installs and blown pinion bearings but this sounds like nothing he's ever heard.

Last night I noticed If i try to rotate any rear tire there is play and the differential rotates back and forth to where the driveshaft moves 3/4 of an inch up and down where it connects to the diff. I do have BMR adjustable LCA's but have never had a problem with them and they have not moved.

Take a look at this picture. You are looking at the left rear right over the caliper. Look at the angle of that bumpstop. Is this normal?

Perhaps one of the two bushings above the differential have worn out or cracked because i can see them flex when I apply force to the rear tires.

Thanks for all help,

-22kart22

brunobluto

My bumpstops sit at the same angle, i think its normal. As far as the noise, my first guess would be the pinion bearing. Its so easy to mess up the install when swapping out gears. But then again, there are so many bearings and critical moving parts located within the driveline, it could be any number of things. I would check to make sure the driveshaft was bolted up right with no problems first. If thats not the culprit, then it probably is within your differential.

sailing220

I had this exact same situation, ended up being a VERY slightly bend axle. The chirping noise was caused by the caliper mounting bracket contacting the rotor during extreme turns and light breaking.

Not saying this is your problem, as it is hard to diagnose based on the information given, but check if anything is contacting your rotors, especially if the noise is coming primarily from one side of the vehicle.

New Moser's fixed it right away.

22kart22

Sailing,

Was your chirping only when turning or consistent? Mine is consistent in every condition

sailing220

Mine was weird as hell. Sometimes it would do it constantly, sometimes only when braking. Some days it would be quiet but louder when turning. Sometimes it would be loud but gone when turning. Some days it was just gone.

The more I compare your situation to mine the more I think it isn't the same problem.

BUT, if you want to be sure find somewhere that will put your car up on a lift and watch the wheels with the car running. See if the hub is rotating evenly or if it is lopsided.