Fox T-Bird/Cougar Forums

Technical => Drivetrain Tech => Topic started by: BobNorway on June 23, 2006, 11:54:47 AM

Title: Where to measure 7.5 or 8.8?
Post by: BobNorway on June 23, 2006, 11:54:47 AM
I've read through all the posts about 7.5-8.8 swaps,
and looked at the pictures and diagrams.
What I'm wondering is what I have on my car.
VIN:   1FABP62FXHH148944
Its an early 87 Tbird LX with 5.0ltr and an AOD.
I do have the 10 inch drums (flat not hat shaped).
Where do I measure 7.5 or 8.8 inches?
The tag says 'AX' which is defined as   a 2.73 8 inch
with no mention of number of splines.
8 inch is pretty much in the middle of 7.5 or 8.8 at least in my head?

Most of the discussions are about swaps and axle lengths.
Buying used junk, unseen, and freight to Norway doesn't seem a good idea to me.
I'm going to make my one wheeler into a posi.
Either with Ford racing FMS-M-2404-F288 or an
Eaton 19605-010.
Has anybody done this rebuild?
Title: Where to measure 7.5 or 8.8?
Post by: thundergrowl on June 23, 2006, 12:06:13 PM
The LX should have the 7.5" More info. (http://"http://www.coolcats.net/tech/general/axleinfo.html")
 
EDIT; the 7.5 and 8.8 are the measurements of the ring gears inside the dif.
Title: Where to measure 7.5 or 8.8?
Post by: Sick88Tbird on June 23, 2006, 12:22:09 PM
The 7.5" cover looks like a circle that somebody cut off the top and bottom of...the 8.8" rear looks more round.  They are both 28-spline units...an 8.8" from a mustang GT or 5.0LX bolts right in and it has a posi.
Title: Where to measure 7.5 or 8.8?
Post by: Thunder Chicken on June 23, 2006, 02:07:56 PM
Quote from: Sick88Tbird
The 7.5" cover looks like a circle that somebody cut off the top and bottom of...the 8.8" rear looks more round.  They are both 28-spline units...an 8.8" from a mustang GT or 5.0LX bolts right in and it has a posi.

Wrong. No Ford has ever had "Posi". They have traction-lock :D Posi is a GM thing...
Title: Where to measure 7.5 or 8.8?
Post by: Chuck W on June 23, 2006, 02:17:26 PM
It's most likely a 7.5

Also, the axle tubes on the 7.5 rears are 2.75" in dia whereas the 8.8's are 3" in dia.
Title: Where to measure 7.5 or 8.8?
Post by: Sick88Tbird on June 23, 2006, 02:22:38 PM
Quote from: Thunder Chicken
Wrong. No Ford has ever had "Posi". They have traction-lock :D Posi is a GM thing...


Yes, I am aware that it's called a traction-lock...#1-I'm lazy, #2-Still some GM parts of me that haven't died yet...I'll strangle them off eventually. 

GM  ~  ME
:flame:
Title: Where to measure 7.5 or 8.8?
Post by: BobNorway on June 24, 2006, 01:19:00 PM
Thanks guys,
Now I know I have a 7.5
No room for an aftermarket "Traction Lock"
One wheel on ice and snow doesn't hack it.
What year Mustang are those on?
Won't they have 5 lugs? My spare tire would be a 9 ha ha.
Title: Where to measure 7.5 or 8.8?
Post by: Beau on June 24, 2006, 05:54:59 PM
you can use an 8.8 out of a fox Stang, but it will be too narrow...
The best bet is a reae from a '94-98', BUT it IS the 5 lug setup...course, then you only gotta do the fronts that way :giggle:
Title: Where to measure 7.5 or 8.8?
Post by: Thunder Chicken on June 24, 2006, 06:53:48 PM
Quote from: BobNorway
Thanks guys,
Now I know I have a 7.5
No room for an aftermarket "Traction Lock"
One wheel on ice and snow doesn't hack it.
What year Mustang are those on?
Won't they have 5 lugs? My spare tire would be a 9 ha ha.

You can install a factory traction-lock unit into your 7.5" - any 83-86 Turbo Coupe or XR7, 87-88 Sport or 87 XR7 would have factory 7.5" traction lock, as well as some Ford Rangers, Aerostars, and pre-86 5.0 Mustangs.
Title: Where to measure 7.5 or 8.8?
Post by: Haystack on June 24, 2006, 09:57:27 PM
You could also get a 7.5 with traction lock out of a mark7, but they are 5 lug. You could always just swap out the spindles.
Title: Where to measure 7.5 or 8.8?
Post by: BobNorway on July 03, 2006, 06:10:35 AM
Guys, does this look correct?
Ford 7.5 Traction Lock from Bryant Motorsports
EBay item 8054727805
Title: Where to measure 7.5 or 8.8?
Post by: BobNorway on July 07, 2006, 03:08:16 AM
Ok I did it!
Got a new Traction-Lok comming from Roland Bryant at Bryant Motor Sports.
Very helpfull guy.
More on this swap when I recieve it.