How do I tell what rear end I have?

there may be a metal tag on one of the rearend cover bolts.

Auto trans 87-88 Tbird Turbo Coupes come with 3.73 gears and manual Turbo Coupes come with 3.55 gears. Cost is $125-$300 for the rear axle. Add another $100-$200 or so to complete the brake upgrade.

Five lug Turbo Coupe conversion:
Use the 94-95 axles Mustang axles. Use 1990 Mazada MPV 3.0 V6 front rotors (10", 5 lug x 4.5" pattern, 2 7/16" offset ). While you are at the auto parts store, set a TC rear rotor side by side with the Mazada rotor and they are the same except for the offset.

The next step fixes the offset problem:
Use a Maximum MotorSports 1/8 spacer (MMWS6, http://www.maximummotorsports.com/i...roduct_info&manufacturers_id=&products_id=576 ) between the inside of the rotor and the axle flange. The spacers may need to have the OD machined to fit properly. The stock rotor offset is 2 5/16" and the Mazada rotors are 2 7/16" offset. The 1/8" spacer puts the rotor back dead center alignment with the calipers.

I usually just look in a mirror because when you ask someone else to examine your rear end they tend to exaggerate.

You likely have a T-Coupe rearend or brake parts. You could possibly have some Mark 7 parts but I'm sure you don't have any Mark 8 parts on your Mustang as they do not interchange.

If your brake bias is not correct (example - rear brakes or front brakes locks too quickly or won't lock at all) then you need an adjustable proportioning valve to get the bias right. These are sold many places. Try Summit or Jegs.

For pads and rotors, Just take one off and take it with you to the parts store for matching purposes. Most of the time it is beneficial to do this even for original parts.

A 5-lug conversion is not necessary for replacing brake pads / rotors unless you want / need bigger brakes or better stopping power. SN-95 stuff is the way to go for the front if you are budget minded. Then you would have to purchase different wheels.

Here's the whole deal on Turbo Coupe rear end swap...

Identifying a Turbo Coupe rear axle:
1.) Measure the rotors - a TC disk brake uses 10 5/16" vented rotors.
2.) Measure the length of the quad shock mount arm and compare it to the mount on your existing stock axle. The TC quad shock mount arm is about 8" long if I remember correctly.
3.) Measure the distance between the axle flanges and compare it to stock. The TC rear axle assembly is 3/4" wider per side, or 1 1/2" wider for both sides.

Been there and done that! With success!

Auto trans 87-88 Tbird Turbo Coupes come with 3.73 gears and manual Turbo Coupes come with 3.55 gears. Cost is $125-$300 for the rear axle. Add another $100-$200 or so to complete the brake upgrade.

I choose 3.55 since I do more highway driving. Both ratios have 10 5/16" disk brakes with vented rotors as standard equipment.

It takes 2 guys the first day to get the old rear end out and the new one bolted in place. It takes 1 guy another whole day to do the brakes.

You will need a several sets of fittings, I recommend that you get them from Matt90GT's website, http://www.svo73mm.cjb.net/. Read Matt's instructions thoroughly, everything you need to know about the brakes is all there. You need to be patient and follow all the internal links, and there are many of them. You will need 2 fittings in the rear to adapt your old brake tubing to the TC disk brakes. The fittings go between the steel tube and the caliper brake hose. You will need another set of fittings to make a 2 port to 3 port adapter. To make life simpler, just buy the kits from Matt. You could piece them together, but it's not worth the time unless you work at an auto parts store with all the fittings ever made.

You will need to drill the quad shock mounting holes 2” below the holes drilled for the Turbo Coupe mounting points. The bolts are metric, so don’t loose them or the nuts. A 15/32” drill should be about the right size unless you have access to metric sized drill bits. Going without quad shocks is not an option unless you have aftermarket parts to soak up the wheel hop.

You will need a proportioning valve, Summit has one for $40 + shipping.
You will need a kit (FMS makes the part) to gut the stock proportioning valve, Summit also has that, about $10.


You will need a new master cylinder, see Matt's site and make you choice. I used a 94-95 Mustang master cylinder. Note that rebuilt 94-95 Mustang master cylinders do not come with a reservoir. That means a trip to the junkyard and some more money spent.

Your brake pedal may be very hard and almost impossible to lock up the brakes. I had to replace the front calipers with 73 mm calipers from a 91 Lincoln Mark 7 to get the braking performance up to par.

Bleeding the brakes will require 2 people and some coordinated effort. I don’t recommend using you wife or girlfriend to pump the pedal – they get offended when you yell at them. I used a homemade power brake bleeder constructed from a garden sprayer and some fittings from Home Depot. It cost about $25 and was worth every penny. See http://forums.stangnet.com/showthread.php?p=6143048 for details and pictures.

See http://www.mustangcentral.net/tech/brake.html for help with the emergency brake. The red words link to some very useful photos on how to modify the handle. The stock setup tends to lock up and not release properly.
All in all I have been very pleased with the results.

88StangLX50 said:

How do I make the E-brake work? I have the ''93 cables but it won''t pull the caliper in. Do I have to weld the sprocket on the E-handle or something?

Click to expand...

Re-read my last post. The last paragraph gives a link that shows how to modify the brake handle mechanism.

jrichker said:

Re-read my last post. The last paragraph gives a link that shows how to modify the brake handle mechanism.

Click to expand...

I did not modify my 82 e-brake but i think i read on Matts site that early Foxes did no tneed this mod. I used the cables that matt recommends for early foxes. I want to get back to stock track so I will be buying the north cobra's brackets then converting to 5 lug.

See Matt90GT's website, http://www.svo73mm.cjb.net/ for your answer. Best Mustang brake site on the Internet.