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Topic: 8.8 rebuild and install (Read 2028 times) previous topic - next topic

8.8 rebuild and install

I have a 87 Cougar. I would like to build a 8.8 but having some trouble getting the info i need to figure out what year of mustang to get it from. I have read up on this for a few weeks and it is kind of hard to find info that doesn't conflict with other info i read in other places. Over the weekend i got some 7.5 axle shafts and backing plates so i can mock it up before i get it rebuilt and tear my car apart. I have read that you can get a 86-93 drum brake 8.8 and use the cougar/tbird axle shafts and brake backing plates and it will work the housings are the same but the axle's were longer and the backing plates were different to take up the difference. But also have read that it only works on the 86-83 tbird's and cougars that the 7.5 in the 87-88 had a wider housing. I have also read that the 94-98 housings are the same width as the 7.5 in my car but they are disk brake 5 lug and i really want to keep 4 lug because i have brand new brakes in the front and i really like fox 10hole wheels. I was also wondering if you can bolt up the drum backing plates to a 94-98 housing with disk brakes. I have read alot of the 8.8 thread in the greatest hits section but alot of the info seems to apply to the 8.8tc axle and i haven't seen one of those in the jy for a long time. When i figure out what axle i need to find i will post pictures of the progress and what i ended up doing to help people with this issue in the future.

8.8 rebuild and install

Reply #2 –
According to the chart on page 6 if you could find the backing plates from a 93-95 then your 86-88 shafts will work in a foxbody housing. If you use 86-88 backing plates you have to shim it correct?

8.8 rebuild and install

Reply #3 –
The only real drop in, correct width, drum brake 8.8 is from an 88 Cougar XR7. They are hard to find. I have one under my Thunderbird.

Also the 85.5-88 Thunderbird/Cougar 7.5, the 88 Cougar XR7 8.8, and the 87-88 Turbo Coupe 8.8 use the same axle shafts. The axle shafts are the same length as the axle shafts for a 93 Mustang Cobra. For example I have an 88 Cougar XR7 8.8 under my Thunderbird with Moser 31 spline axles for a 93 Cobra. They fit perfect.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

8.8 rebuild and install

Reply #4 –


This is on page 6 of the 8.8 trouble sticky, I didn't see it until i became a member but acording to this the early tbird and cougar rears were the same width as foxbody mustangs so the differnce was axle shafts and backing plates unless im missing something.

8.8 rebuild and install

Reply #5 –
Look at measurement B. The 86-88 Thunderbird/Cougar 7.5 rear (and 88 Cougar XR7 8.8 rear) housing is physically wider than the Mustang version.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

8.8 rebuild and install

Reply #6 –
Basically the Fox 5.0 Mustangs (87-93) and the SN95 V8 Mustangs (95-98) all have the same 8.8 housing.  The Fox cars have shorter axles than the SN95 cars due to the exciter rings for the ABS which is roughly 0.75" per side.  The 93 Cobra utilized the TC rear end as that is what Ford had on the shelf and it bolted into the car thus giving it disk brakes.  The overall issue you are going to have is by utilizing a Fox Mustang 8.8 (non-Cobra) brake to brake it will move your current wheel / tire combo inboard about 0.75" which IMO does not look right.

You have a couple of choices of which are find a TC rear end, change to a different wheel with the correct offset to make up for the 0.75", switch to an SN95 rear end which would necessitate either going to five lug or simply having the axles drilled for the 4 lug pattern and drilling the rotors for the four lug pattern.  We would all agree that fining a TC rear would be the way to go if you are going to stay four lug but the SN95 rear are much more plentiful.

I checked on the parts stores online and they show two brake drums for the 87-88 cars of which one is 1-3/4" wide and the other is 2-1/2" wide so there is your 3/4" per side.  If you look at all the vehicles the 2-1/2" drum is compatible with I would guess that you could find a donor car for the backing plates and all the hardware but you would have to find one with the same length axle and axle housing as the Fox Mustang.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp
 

8.8 rebuild and install

Reply #7 –
I found me a rear end out of a 97 mustang gt this weekend i got it tore down to just the housing and the gear carrier right now I see the problem here with the axle's and brakes. looks like with stock bearings it rides just on the edge of the bearing surface of the axle shaft. So i will be buying the repair bearings. One thing im going to try for the brakes is using drums from a 84 cougar. they are differn't then the 87 ones they are wider but they have the same inside diameter as the 87 cougar so if that works i will let you guys know but i bought the last 2 drums off rock auto and all the local parts stores were special order so this might not be the easiest way to do this if it works. I plan on keeping the 5 lug disk parts for later down the road. my car has brand new front breaks and new tires on 10 hole wheels so i want to keep this setup for awhile. I will post some pictures of the progress later and let you guys know how this ends up going for me.