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Topic: Differentiating differences in differentials... (Read 1630 times) previous topic - next topic

Differentiating differences in differentials...

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.

Re: Differentiating differences in differentials...

Reply #1 –
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.
http://www.coolcats.net/tech/general/axleinfo.html
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Re: Differentiating differences in differentials...

Reply #2 –
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.
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Re: Differentiating differences in differentials...

Reply #3 –
yeah that is what I ment.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com