• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

4 lug rear disc brakes

  • Thread starter Thread starter payupsucka
  • Start date Start date Jul 16, 2004

payupsucka

Member
Sep 28, 2003
324
0
16
Keeping it grimy in Fall river MA.
Jul 16, 2004
#1
  • Jul 16, 2004
  • #1
does any one make a 4 lug rear disc conversion i want rear disks but i dont wanna get rid of my pony wheels so an sn95 conversion is out lemme know fellas thanks

jim
 

Euphoric306

New Member
Apr 5, 2004
905
0
0
Jul 16, 2004
#2
  • Jul 16, 2004
  • #2
get one off a tbird turbo coupe, ugh i get tired of recommending that one but its really goood.
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
2,813
234
Dublin GA
Jul 16, 2004
#3
  • Jul 16, 2004
  • #3
Been there and done that! With success!

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.

Auto trans Turbo Coupes come with 3.73 gears and manual Turbo Coupes come with 3.55 gears. I choose 3.55 since I do more highway driving.

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 8 to get the braking performance up to par.

See http://www.mustangcentral.net/tech/brake.html for help with the emergency brake. The ebrake handle on 87 and later models must be modified by removing the spring, and tack welding the pawl and ratchet assembly.

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.

All in all I have been very pleased with the results.
 
C

custom89stang

New Member
Dec 9, 2003
705
0
0
Seattle, WA
Jul 16, 2004
#4
  • Jul 16, 2004
  • #4
either that or they sell a kit for 700$..........either one is fine but i'd go with the t-bird..remember it has a wird axle...nothing that should matter w/ ur pony wheels
 
You must log in or register to reply here.

Similar threads

8
87 lx 4cyl to v8 project 4 lug disc conversion questions
  • 87lx428
  • Mar 24, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
2
Views
501
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Mar 25, 2026
87lx428
8
J
Wheels-Tires Need Some Help - Brakes Upgrade/Wheel fitment
  • jaygee15
  • Dec 8, 2025
  • Fox 5.0 Mustang Tech
  • 3 4 5
Replies
81
Views
2K
Fox 5.0 Mustang Tech May 6, 2026
AeroCoupe
Rear Disc and Rims Offsets
  • TripleYellow
  • Nov 11, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
19
Views
1K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Jan 9, 2026
TripleYellow
Brakes FOX BRAKES ISSUES
  • PonyGTrider
  • Jan 11, 2026
  • Fox 5.0 Mustang Tech
  • 2 3
Replies
53
Views
2K
Fox 5.0 Mustang Tech Jan 31, 2026
Mustang5L5
A
90 Fox 4Lug rear convert to 5 Lug
  • adimice
  • Jun 3, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
4
Views
139
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Jun 6, 2026
limp
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?