hamrad

I think the differential is going bad in my 73 coupe. Was out driving and it started making a clicking noise in the rear of the car. It is really bad when turning. I checked the half shaft u joints and they seem ok. There is no play in the rear wheel bearings as far as I can tell.


I am unfamiliar with the corvette rear ends so need some advice. With the car in neutral, should I be able to turn the rear tires fairly easily? I jacked up the rear of the car and they will turn about a half of turn and then it gets really tight. Also, I removed the fill plug and the rear end oil looks silvery.


So, if this turns out to be bad what are my options?


Thanks for any replies...............

Peterbuilt

Try changing the oil first, get a siphon, some new gear oil and two bottles of GM Limited Slip Axel Lubricant.
Add one bottle of GM LSAL, top it off with gear oil and take a ride and make some figure eights to circulate the oil.

If you have the rear wheels hanging down the half shaft U-joints are binding, raise each wheel and you will be able to rotate the tires.

hamrad

Guess I'll give the oil change a try. The car has set for the last 10 years. I just took it out this evening for a 20 mile drive and the noise just started. Before that it has only been driven a couple miles since I have had it. Got things good and warm this evening.

Have only had the car a short while.

hamrad

Put the car back on the ground and can move straight forward and backward with no noise. Makes a heck of a racket if trying to turn. Hope the new oil fixes it!

71 Green 454

Read this thread:

https://www.corvetteforum.com/forums...diagnosis.html

Good luck.

rworley6641

I had the occasion to assist with this exact same problem with a friend's 1973 3:36. It ended up being the C clip that holds the axle stub inside the housing. The c clip popped off and then got ground into metal slivers by the ring and pinion. With that metal floating around, I would question how long the bearings are gonna last, plus your risking damaging the gears on the ring and pinion. If it were my situation, I would stop now and open the rear cover to inspect. Not an easy task with the rear spring attached; but you might be able to salvage the ring and pinion and cleanup the bearings before the metal filings damage everything. If you let it go on, you could be looking at a total rebuild or buying another rear end. Sorry for the bad news, let us know how it works out so we can all become educated.