How much posi-trac additve should be added to the rear end of a 72 after changing the gear oil?

 

Usually comes in squeeze tubes. Use the whole tube or about a pint. It is a friction modifier for the Posi clutches in the differential.

 

Thanks for the info, I did find out that it takes a 4oz bottle, but for some strange reason, I had to use 2 to make the clutch noises go away. Just curious to the proper amount. It is just fine now.

Thanks, Jim 72 vette

 

if there is not a lot of were on the clutches it will take two bottles of the modifier for the noise to go away, you should be good to go, i know in a eaton locker it takes 3 bottles of modifier for the clicking to go away,

 

Thanks for the info, I have learned not to listed to the charts in manuals. I had to add 2+ of the modifier to satisfy the clutches, but all is well now. Thanks again.

Jim

72 yellow coupe

 

If you have a differential that continues to make noise after adding the limited slip additive, try driving the car in tight circles in both directions. This helps the additive get into the clutch plates and many times will greatly reduce or eliminate the noise.

 

Thanks for the info, will try your idea the next time it is serviced.

Thanks
Jim
72 coupe