Whine when rolling?
 

Hey guys,

My '69 Camaro has an LS1/T56 in it with an ATS trans mount and a 12-bolt with an Eaton posi and Auburn 4.10's. The faster I am, the more noticeable it is - when I am in the throttle, I can hear a "whine" coming out of the rear of the car, and it goes away 100% if I put my foot in the clutch and let it idle. The tone of the whine raises as the car speeds up. It's barely noticeable at 30 mph, fairly loud at 50, and gets pretty damn loud at 80. The car has mono-fiberglass VBP leaf springs in the back.

I measured the pinion angle and found it at +1 degree, with the transmission yoke at 0 degrees, so the pinion angle SEEMS fine, right? The car does not have ANY sound deadener or insulation in it, so the whole car is loud inside - could that noise just be the rear end/gears? I need to change the fluid, and while I've got the cover off I can check backlash.


Thanks for the help,

-Adam

Also, the rear end was rebuilt when the motor was done, about 500 miles ago. I have noticed the whine ever since I got it going with the LS1, and did NOT notice it with the old 350/4-speed/3.08's/no posi. The original driveshaft was used, but shortened by Inland Empire locally.

could be the pinion bearing going bad... Was it a new or used rear end?

new or used gear set?

Definitely ring pinion. I had the same issue at one time. It was new ring but defective machining (Precision Gear Co.)

Also had this issue with one of our company trucks, Nissan with 12bolt dealer warranty.

The whole guts of the 12-bolt are brand new - gears/posi/all bearings/fluids...I'll check out the pinion, thanks guys!!!


-Adam

Sounds like you need to pull the rear end apart and check for proper tooth engagement between the ring and pinion. Reset as necessary. Whoever set up your gears did it wrong. The gears will self destruct if you don't take care of this soon. If your lucky it will only affect the gears and not hurt the housing.