Did a search, but couldn't find the exact info need.

I have a friend that owns a 1993 F-150 5.0L 302 4x4 and is wanting to swap gears. Of course he's unsure what came in the truck stock. I've seen 2.73, 3.08 and I think 3.55 and 4.10, but not sure if these were all stock or if some were aftermarket.

Can anyone tell me where to locate the rear diff code at and the description of the code. I know for the 04-08 F150s they break out like this:

19 — 3.55 non-limited slip
17 — 3.31 non-limited slip
H9 — 3.55 limited slip
B6 — 3.73 limited slip

Thanks!

 

There were many possible stock gear ratios. The first 4 charcters on the bottom line of numbers on the metal tag hanging off one of the rear diff cover bolts is the gear ratio and diff type(open or LS), you'll probably have to remove the bolt to get all the numbers you need.

 

Many thanks! We'll check into this to see what we can find.

Any idea on how these 4 characters may display? Is it something like this:

273O = 2:73 Open
273L = 2:73 LS
308O = 3:08 Open
308L = 3:08 LS

Just trying to get an understanding of what to look for.

 

Axle code is on the drivers door post

12-2.73
17-3.31
18-3.08
19-3.55 (seems like most f150's)
25-4.10
68-4.88


There are 21 possible axles but only the second digit is the ratio code. If it has a letter then it's limited slip, but the last digit will still match up with the ratios given here (B9 is limited slip 3.55). The exceptions are codes 72 and 73which are 4.63 and 5.13 respectively.

 

Typically you'll see 3L55 or 3 55 with a blank space where the L would be. The L of course signifies a limited slip, no letter there means open.

The codes from the door pillar should work as well... Ford Axle Code Chart .: Articles

 

Conanski & cowades:

Thanks! This is why I love this site so much. So many people with the knowledge or at least know where to locate the info at.

We appreciate it. Hopefully we'll post back on Monday with our findings and whether he wants to swap or not.