Axle Interchange/Identification info needed

[Michael Fowler]

OK, The ebay deal fell thru ( seller "says" he sold it locally--but I don't believe him).

Anyway, since I will be junkyard shopping, I need to know what axles will fit in place of my 10.25 Ford ( Sterling).
Also, I need to know what the various axle codes for various years mean.
I think I want a 3.55 10.25. Limited Slip What is the code, and did it remain constant for all years? How new of a 10.25 full floater will fit?

Thanks for the help.

 

[6 Nebraska IDIs]

Up to '97 I know will fit, I wouldnt settle for anything less than the sterling to replace it (ie dont replace it with a dana). The reason I say that is the 3.55 (3.54) geared sterling axles are difficult to find. Limited slip will say LS on the tag.

 

[Mr_Roboto]

I wouldn't bother with a limited slip rear axle. A junkyard LS will be worn out anyways. It will be tight enough to turn both tires by hand, but not enough to be of any use on snow, mud etc. Having owned one new they aren't that usefull when brand new.

Get an open axle and use an L.A. Locker etc that replaces the spider gears.

 

[BigRigTech]

I have a 10.25" LS 3.55 in my F250, the door tag say's C9 if I remember right. Factory posi, works ok in the snow....When she's biten' in the back of the truck will bounce........I also have a 3.55 open 10.25" diff from a 96 F350 - too bad your too far away.

 

[Michael Fowler]

Axle tags are often illegible when they are this old. If legible, I understand there will be a letter "L" in the middle of the ratio, as in" 3 L 55".
What i an looking for is the door VIN plate codes.
I saw codes "39" and "F" yesterday. There was no number following the "F" which I though odd.

OldMisterBill, thanks for that observation. Is there any reliable test that can be done in a junkyard that might tell a good axle from a bad one?

 

[BigRigTech]

http://www.ford-trucks.com/article/idx/0/022/article/Ford_Axle_Code_Chart_.html

The "39" door code is just a open 3.55 diff. I have the same codes on the doors of my 96 F350 and 97 E350 parts mules. one has 10.25" and the other had a 9.75". There is a "breaking" torque for most limited slips, if you know what it is then a beam style torque wrench can be used to see if the LS is still tight by torquing the pinion nut with one wheel locked from turning.

 

[7.3shrk]

How deep do you want to get into it at the junk yard? Drop the cover, and check the gears visually. If they are chipped, or gouged, they will likely need to be replaced. If the oil smells burnt or there is metal in it, the bearings will likely be fried. Grab the diff case. If it moves in and out or side to side, the bearings are wasted, or worse, spun on on the case. If you want to venture into it, take off the hubs and check the housing ends. Make sure they look good and the threads are fine. Good luck,

Nick