I was pulling a huge pine tree out of the ground the other day and i was only in two wheel drive. When I tried to pull it out only the back right(passenger) tire spun. What kind of differential do i have?

 

Easiest way to tell (IMO) is to jack up the rear diff so both tires are on the ground, while in park, or gear. See if you can spin one, or if its really hard to spin one. Easy, smooth spinning means open diff. Hard to spin, means limited slip. Its hard to say based off what youve given. There may just have been more weight on the other side, and less on the one that spun, hense, why it spun.

 

Surely you have a limited slip, or grip in a 4x4. Wouldn't be a 4by if not now would it? Verify this by the sticker on the driver door jam, but I am sure it is a LS unit.

 

Its most likely a limited slip, but depending on your mileage, the unit is probably worn out. Some guys have had luck changing the fluid and adding less of the friction modifier the what ford calls for. It lets the clutch discs in the diff hold better.

 

Hey Robs01F250, you could crawl under the truck and check the tag that's attached to one of the rearend bolts. The bottom row of numbers will start with the ratio id. Usually the first number is under the bolt. But, you should see something like 3 55 3L55 or 4 10, 4L10. The L means it is limited slip and the number is the ratio, 3.55 or 4.10. If the tag isn't there, then you'll have to jack up one side and see if the tire turns. If it does, it isn't limited slip or the clutches could be worn out. Hope this helps. Good Luck!

 

Don't you mean off the ground? 'cuz if he can spin them while they're on the ground, I might be scared to shake hands with him!

 

HAHA good catch, it was what, 1 am? On the ground... Off the ground... What is the difference anyways?

 

Hmm, On the ground... Off the ground... Is that why they call it limited slip?? Depends if it's on or off? Now I understand... LOL