HEATSEEKER
Member!
- Joined
- Jan 16, 2006
I don't see why not, but I'd add the GM posi additive too
No, you don't but GM reccomends it to prevent posi chatter. You could always add it later I guess. Why not do it when you add the diff oil?
I used the Trans-X limited slip additive in mine. It was in Advance auto,in a tube.
My clutches were chattering like crazy when I first bought my GN this summer. After a lube change to Castrol 80-90 and a tube of that additive,the chattering is completely gone.
Steve. '87 GN,t-tops.
Don't know about Castrol synthetic but Iv'e ran Red-Line synthetic rear end lube in my GN for 18yrs. Only been changed 4 times in that time and have LOTS of street miles and MANY 1/4 mile passes and still works flawlessly and Never ANY !! noise of any kind. Oh! and NO other additives period.
PS. I did put new posi clutches in it about 6 years ago.
Thanks Steve!
How mutch do i need? And how mutch oil do the rear axel fill?
No, you don't but GM reccomends it to prevent posi chatter....
2 quarts. Not sure how many litres that is. That includes the additive. So you will have an equivalent amount of oil left over.
I just put half of the first quart in,then put the additive in that bottle,shake...then dump the rest of that qt in.
Is that your Buick Racing video on YouTube? Nice job. Seen it many times. I believe it's up to almost 300,000 hits.
Steve. '87 GN,t-tops.
Over 20 years ago the GM dealers and techs did not recommend posi additive for the GN. It is a friction modifier and allows the clutches to slip.
If it chatters, then the clutches/springs are worn, or some other problem.
For street car use, if chatter is annoying, add it. In cars used at the track, it lessens efficiency and life of the unit.
Don't know about Castrol synthetic but Iv'e ran Red-Line synthetic rear end lube in my GN for 18yrs. Only been changed 4 times in that time and have LOTS of street miles and MANY 1/4 mile passes and still works flawlessly and Never ANY !! noise of any kind. Oh! and NO other additives period.
PS. I did put new posi clutches in it about 6 years ago.
Heatseeker,
No that's to heavy, I run the 75W90 GL-5 and like I posted have for MANY, MANY miles and in all kinds of temps. 30 degrees to 95 degrees. Car runs mid tens and has LOTS of 1/4 mile passes also. NEVER !! had ANY rear end problems, ZERO- NONE. Buy 2 qts. of the 75W90, put it in and don't look back. Personally I'm sold on it.