Terry Burger

iTrader: (4)

I'm having my 4.10s put in, and the gear shop was telling me that my stock posi is a worm gear drive and takes no additive.

He said he verified this with the dealership. Can this be true? I thought all fbodies required the posi additive.

mach1

iTrader: (6)

Yea i've heard that the torsen diff's dont need it, then again i've been told they do. I dont know why they would need it since there are no clutch's in the unit just gears.

Terry Burger

iTrader: (4)

So I have a torsen diff stock?

2000RATA

Yes it's the Torsen. Instead of having a spring loaded spider gear setup you have the worm gear type. While under acceleration it will lock against the clutches. I am almost sure they still have clutches. Looked like it to me when I did my gears. You still need the additive. The owners manual calls it out. The deal with the torsen is now when you go around a corner and you aren't giving it gas you don't have it slipping the clutches like a spring type posi would. It unlocks when the tires spin at unequal speeds or not under acceleration. That is where you could say it doesn't need the additive. But the book still calls for it.

onfire

iTrader: (17)

It's an all gear drive....no clutches....www.gleason.com ...the additive is useful if you hear the worm gears chatter...I used Redline without problems.

[ January 10, 2002: Message edited by: onfire ]</p>

Jay 95WS6

GM has their own specific synthetic Diff fluid for these rears.

Jay

2000RATA

onfire, thanks for the gleason link,.......but I couldn't find a single thing on the GM Torsen carrier. <img src="images/icons/confused.gif" border="0">

SC 98 Mecham

Try this link...
http://www.howstuffworks.com/differential8.htm
No Clutches ! <img src="gr_stretch.gif" border="0">

2000RATA

Thank you! <img src="gr_stretch.gif" border="0"> Goes to show a person can learn something new everyday. <img src="gr_grin.gif" border="0">

12secSS

iTrader: (30)

I remeber a while ago a couple of friends of mine were discussing the same thing. One friend email Torsen and the replied it is not need for the worn-drive unit, but it will not hurt it. Basically if you feel comfortable using go ahead, if you don't want to use it ... no problem. IIRC

Chris Spiess

No clutches in the Torsen and additive is not necessary. Torsen reccomends GL-4 or GL-5 75W-90, mineral or synthetic lubricant. Higher or lower viscosities can be used to alter the bias ratio if desired. They have an excellent white paper on their site desribing the function of the unit. I believe the switch was made in 99 for the F-Bodies - don't know for the Y-bodies tho. GM uses the 'Type 2' unit. SLP also sells the upgraded Type 2 for higher power apps, and there is also a Type 2R intended for road racing applications.

Terry Burger

iTrader: (4)

Thanks gang! I passed on the additive.