I have the tag off my pumpkin and it has S919D stamped on it and some other numbers dont know if they are important trying to figure out if it is limited slip before I chage my axle seal and dump friction modifier in it. If it is LS how much modifier do I add bought 2 bottles from ford. Thanks for any help.

 

need the rest of the numbers those mean nothing should have numbers that form a common ratio like 3.08 or 3.55 or 4.10 and if theres an l separating them like 3l08 you have a limited slip

 

Look at your door tag - if the axle code is 2 numbers it's open, if it's a letter then number its LS.

 

The only other numbers are the second line which read S5 975 9528.
Door tag is missing.

 

Read the tag more carefully - and post all the numbers, complete with spaces. "S5" does not sound right.

What you can do is jack up one rear wheel with it in Park and the e-brake off - try to turn the wheel, if it turns easily it's not LS.

 

I got the back end in the air both wheel turn same so it is limited slip. Thanks for your help.

 

Not necessarily - if you have both wheels in the air, you have to put it in Park or get someone to hold the driveshaft and get someone to hold one wheel while you try to turn the other.

 

Is there not a metal tag attached to a rear housing bolt with something like 355LS if it's 3.55 and limited slip? I'm pretty sure mine is stamped that on a tag.

 

look at the door jam sticker. the axle code should be one of the following.

19 – 3.55 Non-LS
18 – 3.08 Non-LS
H9 – 3.55 LS
B6 – 3.73 LS

 

this is a common misconception this does not mean its a ls as said before you need to leave one tire on the ground and the trans in park/gear, ebrake off and if it still spins easy its open if its hard/imposible to spin its ls

 

Can't you guys read the whole thread before posting?

 

ok it wont turn in park so it is LS right??

 

Go out and peel some rubber, if it only peels one tire, the passenger one I think, you'll have your answer. If both wheels turn and she fish tails to the right a bit, it's a L/S. This is the most fun way to see what you have or don't.