Hi all. Im going to the boneyard sunday and will be looking for a limited slip for my 9" rear. The truck is a 2wd '73 shortbed and was wondering how to ID one in a wreck? Will it fit my 2wd even if the donor is from a 4wd?

appreciated, eddie-

 

I think only some of the lighter 4X4s has 9" rears. Limited slip is not that common in 4 wheel drive. There are two different axles available 28 and 31 spline. Just grab the axles too as you have to pull them out anyway. There can also be differences in the bearings on the axles

I think the axle tag will have a P after the ration for limited slip i.e. 3.50P

 

First, take a look at your 9" housing, center section, etc. Get a good idea what you are actually looking for.

You can use a 9" out of any Ford truck that is after '73. Pre-'73 is too narrow. You could also use an axle from a late model (78+) Bronco.

As to limited slip ID, check the tag on the center section. The tag will identify both the ring gear and the gear ratio, along with some other production info.

For a 9" with a 4.10 gear and limited slip the tag will read as follows:

4L10 9 (then some production numbers)

Or....

If there's no tag, jack the axle up and spin the wheels.



Best of luck on your adventures.

 

Moved to proper forum

The model & tyear of truck doesn't make any difference.The Differential ares are all the same as far as dimensions go.
The differences are the Axle spline amount (28 or 31) & the bearing size for the axles
Ford's application of 9" rears involve more than 5 years .
They can be found
https://www.ford-trucks.com/forums/s...d.php?t=248773