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Topic: Where to measure 7.5 or 8.8? (Read 1926 times) previous topic - next topic

Where to measure 7.5 or 8.8?

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?
BobNorway;)
There are only two tools you will ever need:
1) WD40
2) Duct Tape
If it doesn't move and should, use the WD40.
If it moves and shouldn't, use the duct tape.

Where to measure 7.5 or 8.8?

Reply #1 –
The LX should have the 7.5" More info.
 
EDIT; the 7.5 and 8.8 are the measurements of the ring gears inside the dif.

Where to measure 7.5 or 8.8?

Reply #2 –
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.
Project 3G: Grandpa Grocery Getter-'85 Crown Vic LTD 2-door, 351W with heavily ported/polished GT40 heads, heavily ported/polished Typhoon Power Plus upper & lower intake, Comp Cams 265DEH retarded 1*, FAST EZ-EFI, HD T5, 8.8" 3.73 trac lock with extra clutches, 3G alt. swap, '99 CVPI front brakes, '09 CVPI rear disc brakes, '00 CVPI booster&m/c + wilwood adj prop valve.

Parted & Gone-'88 T-bird Sport, 351W swap, ported GT40 heads

Where to measure 7.5 or 8.8?

Reply #3 –
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...
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 ♣

Where to measure 7.5 or 8.8?

Reply #4 –
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.
Long live the 4-eyes!  - '83 Tbird Turbo - '85 Marquis LTS - '86 LTD Wagon

Where to measure 7.5 or 8.8?

Reply #5 –
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:
Project 3G: Grandpa Grocery Getter-'85 Crown Vic LTD 2-door, 351W with heavily ported/polished GT40 heads, heavily ported/polished Typhoon Power Plus upper & lower intake, Comp Cams 265DEH retarded 1*, FAST EZ-EFI, HD T5, 8.8" 3.73 trac lock with extra clutches, 3G alt. swap, '99 CVPI front brakes, '09 CVPI rear disc brakes, '00 CVPI booster&m/c + wilwood adj prop valve.

Parted & Gone-'88 T-bird Sport, 351W swap, ported GT40 heads

Where to measure 7.5 or 8.8?

Reply #6 –
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.
BobNorway;)
There are only two tools you will ever need:
1) WD40
2) Duct Tape
If it doesn't move and should, use the WD40.
If it moves and shouldn't, use the duct tape.

Where to measure 7.5 or 8.8?

Reply #7 –
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:
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

Where to measure 7.5 or 8.8?

Reply #8 –
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.
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 ♣

Where to measure 7.5 or 8.8?

Reply #9 –
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.
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

Where to measure 7.5 or 8.8?

Reply #10 –
Guys, does this look correct?
Ford 7.5 Traction Lock from Bryant Motorsports
EBay item 8054727805
BobNorway;)
There are only two tools you will ever need:
1) WD40
2) Duct Tape
If it doesn't move and should, use the WD40.
If it moves and shouldn't, use the duct tape.
 

Where to measure 7.5 or 8.8?

Reply #11 –
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.
BobNorway;)
There are only two tools you will ever need:
1) WD40
2) Duct Tape
If it doesn't move and should, use the WD40.
If it moves and shouldn't, use the duct tape.