HHOVette

I own a 76 L48 350 w/th350.
When I'm hard on the gas I get a horendous ratcheting noise from the rear end area.
I thought maybe something was rubbing when the car is under heavy acceleration, but I can't find any rub marks anywhere.
Checked all u-joints, and bearings.
Rear end maybe? I hope not.
any thoughts?????

burners

Does it make any stuttering/skidding noises when you turn tight corners? Is so then that is the clutches in the posi. A gear oil change and some tight turns on a parking lot will fix that.

What about half shaft end play? Or rear wheel bearings? Check the bushing on the front of the diff. Also, the trailing arm bushings.

How lon have you owned the car and how many miles have you put on it?

HHOVette

I've owned it for two years now. got it from my sister in law who bought it new.
It has 56,000.mls on it.
I'm going to try the gear oil change first, It's most likely never been changed.
I did check the half shaft u-joints but I'm not sure what you mean by end play.
The tires sometimes sound like there skidding when making a tight turn at low speed.
Sounds like mabey posi clutches then???

stinger12

I believe he is referring to the yoke endplay - how much the yoke moves in and out of the differential housing. the stock setups are sloppy and you will have more play.

GTR1999

Sounds like clutch chatter. Try the oil change and GM additive first.
The 75-79 diff's require some custom work to make them better and the original clutches are one area requiring attention. I'll PM you a link with some more info.

HHOVette

Great, Thanks