How can I tell if i have a Limited Slip Diff?
 

Is there a way i can tell if i have limited slip diff. on my truck by looking at the Vin number or any other way. Thanks

Check the sticker in the glove box.

If sticker has gone missing, do a brake stand and count how many black marks appear behind the truck.


phox

What sticker do i check in the glove box? Thanks, i was trying to avoid the Brakestand method :cool:

Sticker should be stuck to the inside of the glovebox door.

It used to be under the hood, on a radiator support I think, but in 2000 or 2001 they moved it inside.

There should be a tag on one of the rear differential cover bolts, but I've never seen one myself.


phox

Thanks, i will check it out

I know it's already been said, but this just came up with my rig the other day....power brake and check the black marks [whistle]

I looked in the glove box and there was no mention of any Limited slip diff. Only thing is said was that the truck had 3.55 gears. I have done a couple of burnouts, by accident and there indeed were two black marks left behind. Is it still possible to leave two black marks and not have a LSD? What is a good brand of LSD, i might decide to put one in for better traction in the winter. Thanks

Get your vin #, call your dealer and they can pull up the "build sheet" on their computer and tell you exactly what you have, not only the diff, but everything.

alright, thanks for letting me know, i will do that

The glove box sticker will say 3.55 ANTI-SPIN if you had a limited slip. Another way to be absolutely sure is to use a floor jack or anther method to put both rear tires in the air. Chock the front tires. Put the transmission in Neutral. Release the parking brake. Raise rear end off of the ground. Now spin a tire, and watch the tire on the other side of the truck.

If the other tire spins the same direction as the tire you are turning, you have a limited slip.
If the other tire spins the OPPOSITE direction then you have an open differential.

This is the most sure fire way to know if you have one. Remember, an open diff can be upgraded to a limited slip without having to swap axles.

Thanks for the info, i might try that tomorrow while i put on my new mag hytec covers.

Oh, if you are going to have the covers off you can see the what you have without having to do the tire spinning trick I posted.

Here is what the limited slip looks like (thanks to handymantim for the picture)

https://www.dieseltruckresource.com/...CN5432-med.jpg

Here is what the open differential looks like (thanks to hoot for the picture)

https://www.dieseltruckresource.com/...18DSCN5333.jpg

The center section of each differential is very different, and easily distinguished with the cover off.

Shoot, i wish that i had seen the pics before i put the new covers on, i am trying to rack my brain as to what it looked like. When i opened it up, i dont remember it looking like the bottom picture because that picture looked alot like the diff on my 98 ford ranger i use to have. When i opened up the rear, i thought to myself, hmmm this does not look like the setup that my ranger had? Well thanks for posting the pictures, i appreciate it. The front diff deffinetly looked like the bottom picture. I looked at the tag in the glove box on my dads truck and his said Rear Diff Anti Spin. The sticker in my glove box does not say anything like that. My dad like the covers so much, that he is ordering up a set for his truck.

hmmmm
 

I keep seeing this post.
just dig out one mark or two marks, field or a wet road or a front yard.
Do not break the law

The tire trick would be the best bet at this point know for certain.