Limited slip or posi HELP PLEASE

[NH856]

I'm looking to buy a 1999 Chevy Silverado 2500 Crew Cab Short bed 4x4. It's the old body style and a very rare truck, my only issue is I don't know what kind of 4x4 it has. I own a Z71 and it's limited slip in both axels, so when I put it to the floor in mud all 4 tires are going to spin. I've hear of non-z71 4x4s that when you do that only the back right and the front left will spin. I just want to make sure I'm going to get the most out of my 4x4. The truck is push button 4x4. So does anyone know if the truck is going to be limited slip, posi, solid axel or what. Thanks much appreciated.

[ifixedit]

Limited slip and posi are basically one in the same, just different terminology. There's no such thing as a "solid axle" on a production vehicle and is generally a very old school idea once reserved for racing applications where the plan was to only go straight down a track, if it had one you'd have a heck of a time getting the thing to go around corners. If it doesn't have posi (i.e. a limited slip rearend) you will know when you hit the gas on a slippery surface, only one rear tire will spin. Posi rear ends are usually something the dealer will specify at the time the truck was ordered, so it may or may not have come with a posi rear end depending on what they ordered and is not necessarily based on it's model designation.

 

If it doesn't have posi, look into a Detroit Locker, they'll have one to fit your application.

[NH856]

Limited slip and posi are basically one in the same, just different terminology. There's no such thing as a "solid axle" on a production vehicle and is generally a very old school idea once reserved for racing applications where the plan was to only go straight down a track, if it had one you'd have a heck of a time getting the thing to go around corners. If it doesn't have posi (i.e. a limited slip rearend) you will know when you hit the gas on a slippery surface, only one rear tire will spin. Posi rear ends are usually something the dealer will specify at the time the truck was ordered, so it may or may not have come with a posi rear end depending on what they ordered and is not necessarily based on it's model designation.

 

If it doesn't have posi, look into a Detroit Locker, they'll have one to fit your application.

That's what I've been reading the more I look into, thank you very much!!

[Squirrely]

If the rear has a locker it will have the G80 - Locking Rear Differential RPO code. Look in the glove box.

 

The front is always open diff unless someone put a locker in it. Highly unlikely. You'll know when you try to turn a fully locked 4x4... they're made to go straight. Corners are bad.

 

 

 

Your rear axle is a solid axle assembly.

[Z45]

Posi is short for Positraction, Chevrolets name for its Limited Slip Differential used back in the days of muscle cars, 1950 thru the 70's.

 

Back in the old days each OEM had a name for its limited slip differential

Olds - anti-spin

Buick - Positive Traction

Pontiac - Safe-T-Trak

 

The ONLY GM truck or SUV to use a limited slip differential (Dana rpo G86) was the Quadrasteer models. All trucks and SUV's with G80 use a Eaton (mechanical) Locking differential.

 

Note - G80 is the option code for both.