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Rear end out of a Thunderbird?

  • Thread starter Thread starter blown 91
  • Start date Start date Apr 30, 2004
B

blown 91

New Member
Aug 30, 2001
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Thunder Bay ,Ontario, Canada
Apr 30, 2004
#1
  • Apr 30, 2004
  • #1
Will a 8.8" rear end out of a 89 Thunderbird fit into a 91 LX?
 

trbkrb

Founding Member
Jun 4, 2001
1,976
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39
Houston, TX
Apr 30, 2004
#2
  • Apr 30, 2004
  • #2
No. The 89 up T bird is an independent rear suspension, and is a different chassis design. The 87-88 Turbocoupe is a bolt in with a few mods, since it is the last of the Fox based TBirds.
 
B

blown 91

New Member
Aug 30, 2001
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0
0
Thunder Bay ,Ontario, Canada
Apr 30, 2004
#3
  • Apr 30, 2004
  • #3
OK, thanks. I'm looking for a 8.8, and a "friend of a friend" said he had a 8.8 out of a Thunderbird that would fit..........apparently he doesn't know what he's talking about.
What kind of mods are required to fit a 87-88 Turbocoupe rear end into my 91?
Are those my only options for the Thunderbird rear end? (87-88 Turbocoupe)
Thanks
 

trbkrb

Founding Member
Jun 4, 2001
1,976
4
39
Houston, TX
Apr 30, 2004
#4
  • Apr 30, 2004
  • #4
Here is the page that I used. It has info on the mods:

http://www.geocities.com/motorcity/pit/2740/reartech.html

If you plan to use the disc brakes, look at Matts website also: http://svo73mm.cjb.net

The solid axle 8.8 is only in the 87 & 88 Turbocoupes. All the others pre 89 are 7.5 difs. I have seen info on the 89 up T bird rear used in the Factoty Five Cobra replicas, but they use some special brackets and such to mount it to the car.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,260
17,944
224
Massachusetts
Apr 30, 2004
#5
  • Apr 30, 2004
  • #5
The 89+ T-bird IRS is still an 8.8. It's the design Ford stole and used on the 99+ Cobras. No it will not bolt onto a Fox body.
 
B

blown 91

New Member
Aug 30, 2001
15
0
0
Thunder Bay ,Ontario, Canada
Apr 30, 2004
#6
  • Apr 30, 2004
  • #6
Thanks
 

blkstangman88

New Member
Apr 6, 2004
646
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0
May 1, 2004
#7
  • May 1, 2004
  • #7
check the rear ends b4 u get them, my rear axle basicly blew up on the freeway so i had a shop put a new one on from a t-bird, well now only one tire spins all the time, is there no limited slip or posi? just a quick thought.
 

trbkrb

Founding Member
Jun 4, 2001
1,976
4
39
Houston, TX
May 1, 2004
#8
  • May 1, 2004
  • #8
blkstangman88,

Have you checked to see if the clutches are worn out? The TC rear ends I've seen do have traction loc, so more than likely all you need is the >$50 rebuild kit to fix it. Remove the cover and see if it has the "S" spring in the center and the clutches on either side of the spring. Most of the TC rears did not see a lot of power, but of course maybe yours did wear out. Mine is so tight I think the ds wheel starts spinning before the ps one. Anyway, good advice to check any rear end out thoroughly.
 

blkstangman88

New Member
Apr 6, 2004
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May 1, 2004
#9
  • May 1, 2004
  • #9
the axle only had 10k miles on it, are the clutchs suppose to wear out that fast?
 

trbkrb

Founding Member
Jun 4, 2001
1,976
4
39
Houston, TX
May 1, 2004
#10
  • May 1, 2004
  • #10
No, they should last a while longer, unless they are not installed correctly, or were abused. Mine had 225,000 miles on it when I replaced it with the TC rearend and it still worked fine.
 
B

blown 91

New Member
Aug 30, 2001
15
0
0
Thunder Bay ,Ontario, Canada
May 2, 2004
#11
  • May 2, 2004
  • #11
Sounds like the Thunderbird rear end isn't the way to go. I don't want the extra width anyway.
Thanks
 

trbkrb

Founding Member
Jun 4, 2001
1,976
4
39
Houston, TX
May 2, 2004
#12
  • May 2, 2004
  • #12
It is only wider IF you use the TC axles. There are others that have used the Fox axles and modified the caliper bracket to mount on the inside of the flange, bringing the caliper in about .75". Also www.northracecars.com sells a bracket to mount the TC calipers on the stock Fox axles.

If you need an 8.8, and you can get a TC rear end, it will come with 3.55 or 3.73 gears already, so you can modify the disc brackets, or even use your stock axles and drum brakes on it. If you want gears, and need a new 8.8, then the TC is a great budget way to go. I got my bare TC rear end (no disc hardware) for $60, sold my old one for $40, so I got the 3.73 gears basically installed for $20!
 
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