rearend quest

[R/T kota]

okay so now i am lost, LSD and posi are the same thing then?

Yep

 

[85 Cutlass Brougham]

okay so now i am lost, LSD and posi are the same thing then?

Yes they are. Limited Slip Differential is the generic term, Posi Traction is a marketing term just like Twin Grip (AMC), Traction lock (Ford), Safe-T-Trac (Pontiac), etc.

 

[R/T kota]

posi became the preferred word among car guys the same way as every portable tape player in the 80s was called a walkman even though only sony used the name.

 

[78mali350]

i was gonna say cause i always heard it called a posi haha making more sence now

 

[R/T kota]

i was gonna say cause i always heard it called a posi haha making more sence now

Ya the only guys out there that are anal about the term is the mopar guys. They will almost always correct you and say its a sure grip or whatever they call it.
Any GM car with limited slip tags or codes will be a "posi"

 

[R/T kota]

In the 1950s and 1960s many manufacturers began to apply brand names to their LSD units. While Packard pioneered the LSD under the brand name "Twin Traction" in 1956, the most famous of these was Chevrolet's "Positraction". Since then, Positraction (often shortened to "positrac" or merely "posi") has become a genericized trademark for LSDs.

Other factory names for LSDs include:

* Alfa Romeo: Q2
* American Motors: Twin-Grip
* Buick: Positive Traction
* Chevrolet/GMC trucks (after 1973): Gov-Lock
* Ferrari: E-Diff
* Fiat: Viscodrive
* Ford: Equa-Lock and Traction-Lok
* International: Trak-Lok or Powr-Lok
* Jeep: Trac-Lok (clutch-type mechanical) and Tru-Lok (gear-type mechanical)
* Mopar: Sure Grip
* Oldsmobile: Anti-Spin
* Pontiac: Safe-T-Track
* TVR: Hydratrak

 

[81_2dr_bu]

well thanks for the info everyone clears up alot have to check mine friday