Posi Track

[Zekelefreak]

Okay so I have a 2000 GMC Sierra 1500 stepside with a 4.3L. Not sure what type of transmission, but I want to swap out the LSD rear end with a posi track. What kind of places would I buy one and for how much?

[Z45]

First a little info.

 

LSD (Limited Slip Differential) is a posi-track. Posi is short for Positraction, a Chevrolet trade name for its limited slip differential that was installed in high performance cars of the 60's and 70's, where it gained notoriety. Note-Each GM division had its own name for their LSD.

 

Trucks do not use a limited slip differential, they use a Locking Differential. Discontinued Quadrasteer being the exception, RPO G86.

 

Unless you can find a complete rear axle assembly in a salvage yard, buying new will likely cost you up to $1000 or more. When you go new, you may have replace a lot other parts inside the diff, such as bearings, maybe ring or pinion, axle? You won't know til its torn apart and the cost could go up with new parts.

 

That's my opinion. Btw - I have owned a few GM cars dating back to the 60s's with posi and I have trucks up to this day with locking rear differentials. Unless you are doing some serious hard-core off-roading, rock crawling or installing monster tires, the oem G80 Eaton locking differential will do just find in normal use.

 

check out this video, it explains difference between the two differentials.

 

 

 

 

G80 is the option code used for both a Limited Slip differential and for a locking differential.

 

Option code for GM truck

G80 Differential, heavy-duty locking rear

 

Option code for GM rear wheel drive car

G80 Differential, limited slip

[wheelsthatgrip]

It depends on which rear end you have in your truck.

 

My 2008 Silverado came with an 8.5 30 Spline open differential. This enabled me to install a G80 locker (Used old Ring Gear, installed new bolts/bearings). It lasted 50K miles until one of the bearing bosses broke on the differential housing. Replaced it with a Yukon Posi-unit.