View Full Version : Differentiating differences in differentials...

05-29-2005, 02:26 AM
The rear end of my '85 is toast. I have an opportunity to pick up a '91 3.8 for cheap, but I need to know if it is a direct swap on the rear ends.

Thanks in advance.

05-29-2005, 07:28 AM
what car is the 91 out of, If it is out of a t-bird/cougar, it is most likely a waste of money. You can get one off of a mark VII(1 1/2" onger) a mustang(About 1 1/2" shorter) But you will have to mesure your rear axel. In 1985 the rears went from the mustang width, to its own width. So it oculd be either a mustang or later t-bird/cougar rear end. Either way it should fit okay. Here is everything that you will want to know.

Thunder Chicken
05-29-2005, 07:41 AM
The '91 rear end is completely different. 89-97 T-Birds and Cougars had an independent rear end, while your '85 has a "solid" rear.

05-29-2005, 08:01 AM
yeah that is what I ment.