Grinding noise in rear end 72 Stringray

[larryjinpa]

;help
Can someone help me out here?? I have a 72 Stingray that has an occasional grinding noise in the rear end when I am going at very low speeds or from a dead stop. Again, it does not do it all the time. I spent quite a bit of $$$ in the last 3 months trying to eliminate it. I have had new brakes, rotors and calpiers installed, new yolks & snap rings, bearings, U joints and have had the differential fluid changed. My mechanic is pretty good normally, but I don't think he really knows what it is. Is there a possibility that the differential needs to be rebuilt???

 

[duke94]

Did he replace all the parking brake springs inside the rear rotors or just the pads and calipers? A common failure is for the PB shoe retracting springs to break due to rust and rub on the rotor.

 

[larryjinpa]

Thank you!

I am not sure. I will ask him though. Thanks for the reply.

 

[JohnGrawcock]

Did you replace all 6 U-joints? When the joints in the half shafts go dry you only notice them groaning at you at low very speeds.

 

[chevy6673]

ok dont anyone laugh, to loud i had a noise from the rearend on my first 73 a guy told me to find a big parking lot and drive in the smallest (tightest) circle to the right and left it worked ,,, mike

 

[JohnGrawcock]

Isn't the curiousity killing anyone else?

ok dont anyone laugh, to loud i had a noise from the rearend on my first 73 a guy told me to find a big parking lot and drive in the smallest (tightest) circle to the right and left it worked ,,, mike

It sounds like your trying to get the limited slip to kick in, but what's it supposed to fix?hnoes

 

[GTR1999]

Could be in the Differential. When you replaced the yokes what was the endplay afterwards? If you have an issue then it will not go away. 72's are pretty good with the original yokes but the later years are softer and they ground down until they hit the housing. That could be one area to look over again. Aother areas of failure in the differential are ring gear bolts, they back out and lock up, spider gears will make noise if they are shot or the case is worn. If it was rebuild by someone who didn't know what they're doing( it happens a lot) then you may have other concerns.
I have a lot of info on this subject if you email me I'll link you to it.
Check the obviouos things like the PB shoes, pad pins, wrong caliper bolts hitting the rotor,etc

 

[chevy6673]

It sounds like your trying to get the limited slip to kick in, but what's it supposed to fix?hnoes

the guy said if the car seats for some time surface rust may build on gears just passing along thought it could not hurt to try ..

 

[larryjinpa]

Thanks for the reply. I will check with my mechanic.

 

[larryjinpa]

Thanks Mike. Someone else suggested that. It is worth a try.

 

[GTR1999]

If the posi clutches are binding the oil change and additive change with figure 8's may help. If it doesn't then you may have to look in the diff. Sounds like you covered all the other areas. Again check the endplay in the yokes.