Positraction additive
Thread Starter
Racer
Joined: Nov 2010
Posts: 296
Likes: 0
From: Vilonia Arkansas
Positraction additive
Will it damage the rear differential if too much positrack additive is added to the lube? A friend changed mine when I wasn't there and was unaware that it required only 4 oz and he put in the whole bottle. Do I need to change it again and add the correct amount of additive?
Thanks.
Thanks.
Racer
Joined: Jan 2011
Posts: 266
Likes: 0
From: York Pa.
The additive is for the posi unit..if the bottle of additive came from GM they are not much more than that..I put the whole bottle in mine..you don't get all of it out of the bottle anyhow so I wouldn't worry about it..what type of fluid..GL 5 did you put in..some already have some friction modifiers in them..
Thread Starter
Racer
Joined: Nov 2010
Posts: 296
Likes: 0
From: Vilonia Arkansas
Got the lube and additive from Auto Zone...can't remember at the moment the brand, but I know the bottle of additive was well over 4 oz. I'm thinking it was probably a 16 oz bottle.
Thread Starter
Racer
Joined: Nov 2010
Posts: 296
Likes: 0
From: Vilonia Arkansas
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Drifting
Joined: Jul 2002
Posts: 1,995
Likes: 110
From: Garland Texas
No it won't hurt anything. If he used GM gear lube one bottle is sufficient. If he used non-GM lube then more then one bottle is needed. The additive is only a friction modifier for the clutches.
Mike
Mike
Thread Starter
Racer
Joined: Nov 2010
Posts: 296
Likes: 0
From: Vilonia Arkansas
Thanks fellas.
So if I use a GL-5 gear lube I don't need an additive? If so, I'll probably suck some of what's in it out and replace it with GL-5 and be done with it and have peace of mind.
So if I use a GL-5 gear lube I don't need an additive? If so, I'll probably suck some of what's in it out and replace it with GL-5 and be done with it and have peace of mind.
Le Mans Master
Joined: Jan 2006
Posts: 6,498
Likes: 136
From: Butler Pa
Drifting
Joined: Jul 2002
Posts: 1,995
Likes: 110
From: Garland Texas
If you run the GL-5 gear lube you need one 4 oz bottle of additive. GL-5 lube has some additive in it. If it is not GL-5 or some off brand like most repair shops use you may need up to 2 bottles. The clutches will tell you have much you need. 8 oz of GM additive won't hurt anything. It has it's own lubricating properties. Too little is far worse than too much.
Le Mans Master
Joined: Oct 2007
Posts: 7,410
Likes: 949
From: Tennessee/Rhode Island
I have used Mobil 1 GL-5 synthetic 75W-90 since 1990 (changed it twice) with no GM additive and the diff has been fine, no shuttering/Chatter, posi unit works perfectly. I would not worry about it either but I also would only use the additive if you are running a conventional diff oil.
Burning Brakes
Joined: Sep 2008
Posts: 805
Likes: 5
From: Naperville Illinois
The stuff from Autozone is likely Trans-X, and it comes in 7 oz tubes. There is absolutely nothing wrong with adding a whole bottle of this stuff to your diff. You can pump it out if you want (only you can put a price on your peace of mind) but I'd drive it for a while first and see if it exhibits any slipping, noise or other issues.
Thread Starter
Racer
Joined: Nov 2010
Posts: 296
Likes: 0
From: Vilonia Arkansas
The stuff from Autozone is likely Trans-X, and it comes in 7 oz tubes. There is absolutely nothing wrong with adding a whole bottle of this stuff to your diff. You can pump it out if you want (only you can put a price on your peace of mind) but I'd drive it for a while first and see if it exhibits any slipping, noise or other issues.
I'm gonna run by Auto Zone and see what I bought. If you're correct, I'll drive it and not worry.
Thanks!
Le Mans Master
Joined: Sep 2004
Posts: 5,116
Likes: 5
From: Livonia MI
Not much a fan of oil additive's myself, and usually just use the proper lube to begin with. Done a few diff build's like this with little problem. Some people complain of posi clutch pack chatter and dump this stuff in. Maybe help's the noise, but most of the posi action's usually gone too. Guess I'm from a school the lube manufactures got it right, and adding more stuff just messes up the engineered chemistry. If you put in to much additive, probably good to start over, and flush out the clutch pack's while you're at it.