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Technical => Drivetrain Tech => Topic started by: ArizonaTC on May 15, 2009, 12:59:56 AM

Title: 88 Thunderbird LX V8 Rear End
Post by: ArizonaTC on May 15, 2009, 12:59:56 AM
Does the 88 Thunderbird LX V8 with digital dash (not the Sport ) come with a 7.5 or 8.8 rear end?
Title: 88 Thunderbird LX V8 Rear End
Post by: vinnietbird on May 15, 2009, 01:07:33 AM
7.5
Title: 88 Thunderbird LX V8 Rear End
Post by: ArizonaTC on May 15, 2009, 01:11:11 AM
Quote from: vinnietbird;272420
7.5


That's not good news, will a complete 87 MKVII rear end bolt in?
Title: 88 Thunderbird LX V8 Rear End
Post by: TurboCoupe50 on May 15, 2009, 11:07:38 AM
a few '88 5.0 Birds had 8.8s just like the Cougars, you'll have to get under it and check....
Title: 88 Thunderbird LX V8 Rear End
Post by: ArizonaTC on May 15, 2009, 11:39:56 AM
Thanks, I've already decided not to pursue the purchase.
Title: 88 Thunderbird LX V8 Rear End
Post by: Sick88Tbird on May 15, 2009, 02:38:19 PM
My '88 Sport only has a 7.5 in it, however it is a traction lock unit.  Go figure.
Title: 88 Thunderbird LX V8 Rear End
Post by: Haystack on May 15, 2009, 10:49:43 PM
If you have the vin you should be able to check the axle code.
Title: 88 Thunderbird LX V8 Rear End
Post by: TurboCoupe50 on May 15, 2009, 10:56:57 PM
Quote from: Haystack;272575
If you have the vin you should be able to check the axle code.

There is not one s of info in a vehicles VIN number that pertains to axle type...

That info is on the data sticker on the door jam ONLY... Even then you'll only get ratio and whether it's Traction Lock or std... You wanna know the size, gotta crawl under it...
Title: 88 Thunderbird LX V8 Rear End
Post by: Lightningbird on May 15, 2009, 11:03:07 PM
I agree with Tom....get the info from the tag on the rearend. That's the best way to do it.
Title: 88 Thunderbird LX V8 Rear End
Post by: Cat Daddy on May 15, 2009, 11:19:08 PM
What they said.Check the door or crawl under and check the tag and cover shape.None of my Traction Lok or whatever they call it diffs have had a tag to identify them a such.
  But they do all have a tag identifying the ratio.
Title: 88 Thunderbird LX V8 Rear End
Post by: 86XR7project on May 16, 2009, 09:44:18 AM
You can also check by rotating one side (A friend of mine told me this so I'm not 100%) if the other side rotates the same direction its a trac-lok if not its an open diff.
Title: 88 Thunderbird LX V8 Rear End
Post by: TurboCoupe50 on May 16, 2009, 10:49:34 AM
Quote from: Cat Daddy;272583
.None of my Traction Lok or whatever they call it diffs have had a tag to identify them a such.
  But they do all have a tag identifying the ratio.

All the Traction Lock rears I've seen, have on the tag 3L25 for a 3.25(or what ever the ratio)... If its a peg leg, the letter will not be there...
Title: 88 Thunderbird LX V8 Rear End
Post by: Cat Daddy on May 17, 2009, 08:20:36 AM
Quote from: TurboCoupe50;272647
All the Traction Lock rears I've seen, have on the tag 3L25 for a 3.25(or what ever the ratio)... If its a peg leg, the letter will not be there...

 You are correct!I did a little research and found out that an L in the code means locker.I believe non lockers have an S in the code.
  I am so used to seeing an additional tag requiring some sort of additive that I missed the letter in the tag.My bad:hick:
Title: 88 Thunderbird LX V8 Rear End
Post by: 86sonicbird on May 20, 2009, 02:19:21 AM
If you are familiar with the cover of the 7.5 and an 8.8 peek under and look at the cover of the rear end and you will know.
Title: 88 Thunderbird LX V8 Rear End
Post by: Live Fast on May 20, 2009, 06:07:33 PM
whats my car got in it? Its positive traction, 88 Sport model. Should be 8.8 correct? I havent got under it to look. (just had back surgery 2 months ago, still cant get under a car)
Title: 88 Thunderbird LX V8 Rear End
Post by: thunderjet302 on May 20, 2009, 09:18:40 PM
Most if not all 88 Sports had a 7.5 TRACTION-LOK ("posi" is a GM/Chevy term ;)) rear. Very few, if any, Sports had an 8.8. If they did they were likely late production run cars that used left over 88 XR7 8.8 rears.
Title: 88 Thunderbird LX V8 Rear End
Post by: Thunder Chicken on May 20, 2009, 10:27:16 PM
There have actually been several confirmed 8.8" drum brake 88 Sports, many of which belong to members of this forum. It's not known how many or for what reason (likely to use up the leftover T-Bird/Cougar-width 8.8" drum rears slated for XR7's, which had the 8.8). Unfortunately the only way to know which type you've got is to get under the car and look...
Title: 88 Thunderbird LX V8 Rear End
Post by: Live Fast on May 20, 2009, 10:52:18 PM
maybe in a month or so i will be able to get under my car. but for now i can only work on the top, today i got new valve covers and gaskets, got rid of the smog pump, and cleaned the intake up and painted it.