So I bought some new tires for my 1998 f150 4x4 that I've owned for 2 years and went out mudding, and got stuck in a hurry. I decided I wanted to get a Locking diff. to give me some better performance. So I needed to know what kind of rear end I had, I am new to rear ends but I don't think I am mistaken here, I think my f150 has a 10.25" rear end. Is that common because I think that is a Heavy Duty rear end. And what kind of gears should I expect with the 10.25"?

also the Locker I am looking at this moment is the Powertrax Lock right Locker, any reason why it wouldn't be right?

note: I'm off road around twice a weak in mud/dirt and snowy situations in the winter.

 

what engine do you have? the 4.2 and 4.6 came factory equipped w/ the 8.8. the 5.4 comes w/ the 9.75. the 10.25 is a seven lug, and only came on the 7700 heavy duty F-150.

 

I have the 5.4, its also 4x4. I came across a site last night that said the 10.25'' came with 4:10 or 4:56, is that true? how can I find out what I have?

Powertrax Lock right Locker?

 

On the diff there is a tag, its on the right side, there will be a series of numbers.. the first ones will say the diff size... for example it looks like 9 75 or 10 25. If you have a limited slip, there will be a 'L' between the numbers... example is 9L75 or 10L25. If you have a 5.4 and it says F150 you have a 9.75. If you have what looks like a F150 but says F250 you have a 10.25. The 10.25 comes with 3.73 or 4.10. Hope this helps you.

 

Is it that metal tag that talks about the kind of grease, or is it a sticker? The sticker said 9O9C. I know its an open Diff, though because I can have two wheels up on jack stands and I can mash the gas in 4 wheel and cant get off the stands. Should I expect an 8.8 in the front?

 

It is a metal tag that is attached to the rear diff, there are 2 of them, one on the left and one on the right, the one on the right is the one you'll want to see. The first number is normally hard to see because the bolt sort of covers it. As for the front diff, all F150/F250 light duty and the 00-03 7700 have the 8.8 front diff.

 

is this your method for getting off of jack stands

 

the front axle on your truck is a 8.8R

does your truck have 7 lugs? or 5? if its 5 then its a 9.75. if its a 7 lug than its a 10.25. If you want to know the gearing then tell me what the code on the door jam sticker says under axle.

 

it says H9

 

you have 3:55 LS (limited slip)