Dakatoagain yes it is misleading, read about the different types of differentials. Now think about having an open differential on a 2wd truck, it is really only 1 wheel drive (whichever wheel has the least amount of resistance).

However, everyone looks at you funny when you refer to it as 1 wheel drive.

 

this is true, ever see someone smoke that 1 tire for 100 plus yards. kinda sucks. but i have the corporate rear that is the much better, both rear wheel grip all the time. an when i put it in 4 wheel drive, all 4 tires grip,

 

Superdak05,

Having a locking rear basically makes you a "3 wheel drive" (2 rear+1 front) in a worst case scenario (unless you have some kind of locker on the front too.) If you have one on the front, I believe you want to only use the ones that are selectable (like the ARB or the ones offered on the Rubicon Wranglers)? My reasoning is that the cornering issues you see wiht LSD's and other automatic locking ones would be exagerated in the front.

 

Your standard no options 2wd vehicle will only spin 1 rear tire when it loses traction due to the open differential. One with a limited slip or locking differential will spin both. On your standard no options 4wd you have an open differential front and rear which means when you lose traction in 4wd one rear tire and one front tire will spin. For more traction on a truck that sees mainly on-road use you can add a limited slip rear.

Offroad you can use lockers but these are less than desirable on the road because your tires on each side need to spin at different rates when you are turning (since the inside tires travel less distance than the outside tires through the turn). You will notice many hardcore off-roaders install locking front and rear differentials which they can switch from locked to unlocked with a switch mounted in the cab.