Which posi does my car have and what oil?
01-09-2008, 08:18 AM
#1
TECH Fanatic
Thread Starter
iTrader: (10)
Join Date: Apr 2006
Location: NJ
Posts: 1,320
Likes: 0
Received 0 Likes
on
0 Posts
Which posi does my car have and what oil? I have noticed this question comes up a lot so I figured I would make a post.
Earlier 4th gen F-bodies came with a Auburn differential www.auburngear.com
Where as later 4th gen F-bodies came with a Torsen differential www.torsen.com
Auburns are a springloaded conical clutch style which work best in conventional (mineral) oil GL-4 rating or higher with the LSD additive. Synthetic oil has a higher sheerpoint which I have been told hampers the effectivness of the conical clutches in the Auburn unit. Therefore it is reccomended to stay away from the use of synthetic oil in a Auburn unit.
Torsens are a torque biasing worm gear unit which work well in either conventional or synthetic oil. Althought the additive is not required, GM issused a bulletin saying if the driver experianced a "Rusty Screw Noise" coming from a torsen differential to add the LSD additive to quiet the noise.
If you dont know which posi you have you can pull the inspection cover and look but an easier way which I can tell the difference is to jack up the back of the car and spin the passenger side forward with the car in gear or park and the drivers side tire spins the opposite way like an open carrier you have a torsen. If they dont spin at all with the car in park, take the car out of gear or park and spin the drivers side forward and you will see that the passenger side spins the same direction than you have a auburn.
Therefore, by simply saying that you should ad two quarts convantional oil with the additive you are covering all your bases if you do not know which carrier you have.
Earlier 4th gen F-bodies came with a Auburn differential www.auburngear.com
Where as later 4th gen F-bodies came with a Torsen differential www.torsen.com
Auburns are a springloaded conical clutch style which work best in conventional (mineral) oil GL-4 rating or higher with the LSD additive. Synthetic oil has a higher sheerpoint which I have been told hampers the effectivness of the conical clutches in the Auburn unit. Therefore it is reccomended to stay away from the use of synthetic oil in a Auburn unit.
Torsens are a torque biasing worm gear unit which work well in either conventional or synthetic oil. Althought the additive is not required, GM issused a bulletin saying if the driver experianced a "Rusty Screw Noise" coming from a torsen differential to add the LSD additive to quiet the noise.
If you dont know which posi you have you can pull the inspection cover and look but an easier way which I can tell the difference is to jack up the back of the car and spin the passenger side forward with the car in gear or park and the drivers side tire spins the opposite way like an open carrier you have a torsen. If they dont spin at all with the car in park, take the car out of gear or park and spin the drivers side forward and you will see that the passenger side spins the same direction than you have a auburn.
Therefore, by simply saying that you should ad two quarts convantional oil with the additive you are covering all your bases if you do not know which carrier you have.
