12 bolt Moser 3.42 Posi.

[Double0me]

This is my First Moser and I am not versed in the setup, question is, it grinds in a hard turn (like in a circle) Its the same in forword and reverse, is that just the POSI or do I need to recheck the install? Thanks in advance.

[Firebirdjones]

Sounds like it needs a bottle of posi additive. What is supposed to be in the gear oil bottles isn't enough.

[Double0me]

Bad Ass! I was thinking it wasnt right and I have been tring not to drive it. Thank you I will try that tomorrow.

[WS6SP33D]

This is why im not a big fans of 12 bolts. You always have a noise and the turning radius is not as sharp. 9" usually give you as close to stock ride as possible. Any info on internals? Age of rear? As firebirdjones said above a little thicker additive works wonders.

[Firebirdjones]

It's not the rears fault. 9 inchers with a clutch style posi will do the same thing. I assume he is running a clutch style unit in his and the first thing that came to my mind is the tiny bottle of posi additive.
It's said on bottles of gear oil that the stuff is already mixed in, but I've found it doesn't work. Every rear I've done had the chatter until I added a sole bottle of the posi additive.

From his response, it sounds like it wasn't added.

[Double0me]

put the posi add. in last week and gave it a few days of light driving and havent had the same grinding sound on a hard turn. Thanks guys!

For search referance,

1999 pontiac Transam 4L60E P1SC moser 12 bolt posi grinding, chatter

[Firebirdjones]

Good to hear. Simple fix.

[02transamce]

I had the same issue with my Moser 12,go get some Ford friction modifier,it stinks like hell so don't get any on ya,the Ford stuff works better than the GM stuff,made a big improvement in my T/A.