Hey guys, I'm wondering if I've got a limited slip or an open diff. There is no "L" code or anything on the door tag and the tag on the diff is too rusty to see anything. But, this is what makes me think that it has a LSD. When I jack one side up off the ground, I cannot turn the wheel...it catches. On my jeep that had an open diff, I could freely spin a wheel with it off the ground. But, tonight, backing into my driveway, there was on the passenger side, a muddy/grassy area, and only one wheel was spinning, making me think open. Can anybody give any insight as to what I might have?

 

Not to sound smarty pants, but was the parking brake off and trans in neutral?

If your diff code does not have a letter in it, then it is an open diff from the factory.

 

Duhhh on my part. Parking brake was off, but it was in park. I'm used to thinking in terms of a stick shift. I hate open diffs and auto transmissions.

 

If you don't have an axle tag or build codes, just jack the rear of the truck up and spin the wheels. What do they do?

Ford's Traction-Lok is not a locking diff, so it's possible to overcome the clutches inside... or it could be worn out.

 

I have a ford traction lock and both my wheels spin on grass the passenger side will spin first then the drivers side locks up and it spins. pull out a couple tree stumps last month so I know it works..