Rear End Fluid Change

[Chris R.]

I'm ready to change the fluid in the rear end of my "new" 64 convertible since I don't know when it was last changed. When I went to the local Chevy dealer he sold me the fluid and positraction lube off the shelf. I would have thought that I'd need specially formulated lubricant for my baby. Is this the correct stuff? If not, where can I get the proper lubricant?

Also, can I suction the fluid out or should I separate the pumpkin to drain the existing lube? If I should have to separate the housing is there anything more than loosening the bolts that I need to do?

Thanks,
Chris Rose
Memphis, TN

[Gary J.]

Re: Rear End Fluid Change

The guys at the chevy dealer sold you the right lube. You can just suction it out. It will not take long to do this. You can jack the car up on the opposite side of the plug so all the lube will run to that side of the plug and then suck it out.

Gary
#3503

[Richard D.]

Re: Rear End Fluid Change

Been wanting to do that since I got my 68 in Dec.

I used synthetic for the trans (M-20) and it shifted better.

I know they sell the Posi additive to add to standard weight lube (75-90?).

I used the Mobil trans lube when I did mine.

Rich

[Ron J.]

Re: Rear End Fluid Change

If you go the route of separating the pumpkin you can remove the bolts but only loosen the top ones before you break the seal...This helps to keep the lube from splashing all over the place and draining properly.
Remember to have the rear end at operating temperature...drive it around the block a few times. The lube is so thick that it will never drain out cold.

Someone recommended to me that after you drain the lube you can use a solvent like break cleaner to clean out any remaining lube and metal shavings.
I have not tried this and don't know if its a good tip or not.

An easier alternative is to drive it over to jiffy lube and have them suction it out.

[William V.]

Re: Rear End Fluid Change

If you use GM fluid make sure you add the GM posi additive. If you leave it out the posi clutches will bind and clunk when making turns.

Bill