I was wondering if someone could decode my rear end tag.

The bolt is on one of the numbers but I'm guessing it is a "3"

The first line is--- S 909 B-1

Second line is --- 3L55 9 75 7m08

On the second line I'm not 100% it's a 3 but I'm guessing

 

I think that it is a 3.55 Limited Slip if Im not mistaken. Im sure someone else will correct me if Im wrong.

 

yeah, thats what i was thinking, but anyone have any clue on the rest of the numbers?

3.55 is stock right?

 

9 3/4 inch, limited slip with 3:55 ratio. That is what the tag says.

 

Your second line says 7m08? It should read 7 (july) m (month) 98 (not 08) is the year. Is this the differential under your truck? If so and yours is a 98, then is your truck a F250 ld (7 bolt wheels)? Is this a later differential you are considering putting in? That is the production date of that differential.

 

This is the stock one for your truck, there are other F150's that came stock with different gear ratios.

 

Yea im pretty sure it said 08, i will double check tomorrow i might have mis read it. it had alot of oil build up on it so i was under there with carb cleaner spraying and wiping it down and i came across the tag, so i might have not clean the 08 part enough, could be a 9?

 

Can you tell me about mine this is the tags

 

The first one is an 8.8 with a 3.31 ratio axle. Is that an L in front of the 31? If so it is a locker. The second I can't read.

 

The other is the front axle