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Topic: tc rear 5 lug conversion (Read 2366 times) previous topic - next topic

tc rear 5 lug conversion

so I was looking at coolcats and it seems to say that with a tc rear, you can use 94-98 mustang axles and 91-92 mark vii rotors, but it did not seem very clear. does anyone know if that setup will bolt right in and work with the tc brake system? thanks
1988 Thunderbird sport
2004 Ford F150 Lariat
2008  Chevrolet Cobalt Sport
2007 Suzuki DR-Z400S dual sport/Supermoto
1988 Thunderbird LX - sold
1988 Mercury Cougar XR-7 with GST kit - gone

tc rear 5 lug conversion

Reply #1
Think they were referring to using the 94-04 Mustang axles, rotors, calipers and caliper mounts. Basically using all the Mustang brake hardware and axle shafts bolted into the TC rear end.  On the TC rear end the caliper mounts that you can unbolt and remove once the axle shaft has been slid out, have a diagonal metal support brace that goes from the caliper mount to the rear axle housing, for additional rigidity and support. Unfortunately, it is welded on both ends for attachment. The caliper mounts cannot be swapped until this brace is cut thru on one end or the other. Its what I did on my 87 TC anyways.

As for the Mark VII rotor swap for the front to accomplish 5 lug, its a fairly straightforward rotor swap but it still utilizes the integral hub and bearing assy which limits wheel options because the hub and dustcap will protrude too far out of the middle of most 5 lug Mustang and aftermarket wheels to allow the centercap to be used. And the brake caliper design is still inferior to the 99-04 SN95 Mustang or Cobra brakes.

Its a bit of a pain and some $$, but better results can be had by using the SN95 spindles and the 99-04 brake components. I used the 94/5 Mustang spindles and just removed the front control arms and swapped them with ones I got off a 2003 Mustang at the Pick and Pull junkyard. They had great looking balljoints and bushings so I just used them instead of buying all new stuff for my old TC arms. They bolted right up and have same measurements.

tc rear 5 lug conversion

Reply #2
I was referring to this portion. like I said, its not very clear. but I am talking about mark vii rear rotors.

1984-92 Mark VII Rear Discs
The Lincoln Mark VII usually had 4-wheel disc brakes but some had drums, so be careful when checking them out. The Mark VII, as with a lot of Lincoln components, had their own unique vented 10.5" rear discs through 1990. This means you would need to use Mark VII rotors, calipers, pads, brackets and bolts. From what we understand it's not simple to do the 1984-90 Mark VII rear disc swap. From 1991-92 the Mark VII had 10" vented rear discs in 5-lug and those would be the ones to get. You could then reuse the other stock Turbo Coupe components.

if 91-92 mark rotors will fit with the tc brakes, what 5 lug axles do I need?
1988 Thunderbird sport
2004 Ford F150 Lariat
2008  Chevrolet Cobalt Sport
2007 Suzuki DR-Z400S dual sport/Supermoto
1988 Thunderbird LX - sold
1988 Mercury Cougar XR-7 with GST kit - gone

tc rear 5 lug conversion

Reply #3
Well, guessin here so dont hold me to it, but if the smaller 91/2 Mk7 rear rotors will work with the stock TC calipers and caliper mounts, then I reckon you'd want to use the 94-up Mustang axle shafts. They are essentially the same as the TC axles except they are 5 lug plus they do have the ABS ring in the same position as on the TC axle shaft so your rear ABS sensors shouldnt have any problem.

When you open the diff to start removing the C-Clips so the axles will slide out, be sure you have a good quality 5/16 closed end wrench on hand for the cross pin bolt. These things can be in there very snug for such a small diameter bolt and its not unheard of to have one shear off inside the diff unit.  When it does, a whole lot of ugly words and unusually high alcohol consumption usually follows.

tc rear 5 lug conversion

Reply #4
I think the better question here is why are you stuck on using the TC braking parts?  Pull the axles and all of the TC braking components off along with all of your front braking parts including the spindles and sell it.  Install the SN95 front spindles and braking (use the 99+ front calipers as they are dual piston) and install either SN95 V6 or V8 rear axles (94-98) and all the braking components and you are done.  The e-brakes will hook right up just like the stock TC calipers.

The reason I suggest this is that you can get all the parts from a salvage yard and then get rebuilt calipers from the parts store as you will have cores.  The SN95 brakes are what our cars should have come with and the braking power versus the Fox garbage is vastly superior.

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


93 331 Mustang Coupe - 368 rwhp

tc rear 5 lug conversion

Reply #5
well I just finally upgraded from the 10" drums so i think this is a step in the right direction and I'm not sure that the rear is justified for me. the fronts I totally understand and might end up going that route for the front portion of a 5 lug conversion. are the rears really that much worse than a sn-95? really like how the tc's have vented rears, never understood why they went solid on sn95s.
1988 Thunderbird sport
2004 Ford F150 Lariat
2008  Chevrolet Cobalt Sport
2007 Suzuki DR-Z400S dual sport/Supermoto
1988 Thunderbird LX - sold
1988 Mercury Cougar XR-7 with GST kit - gone

tc rear 5 lug conversion

Reply #6
I forgot to mention that you need to install a manual proportioning valve to dial in the rear brakes.  You do this by gutting the proportioning valve side of the factory combination valve (brass block below the MC with all of the brake lines going in it) and then install the manual proportioning valve (Google this, search on Mustang sites, hell search here on how to do this).

Unless you are tracking the car the solid versus vented on the rears is not much to do about anything.  So when my 93 Coupe first started life it was a 4 cylinder car with the same horrendous brakes on it as my 83 T-Bird.  Lighter car and they still were completely inadequate.  I swapped over to the 11" front brakes with the Performance Friction Z pads and TC rear brakes (SS Brake Corps equivalent) and it was better but still not what I would call stellar.  A few years later I went to a full 1995 GT SN95 system and had it on the car for over three years and it worked flawlessly and I beat the shiznit out of that car with the Maximum Motorsports suspension.  I did install the 99+ dual piston front calipers on it about a year into that version of brakes and holy hell what a difference compared to the single piston setup.  Then I moved to the Cobra setup and the difference was more noticeable than going from the 4 cylinder setup to the TC setup but not anything like going from the TC setup to the SN95 GT setup.

So from experience (the Bird has a full Cobra setup on it as well) I can tell you without any hesitation if you are going five lug skip all the bullshiznit and get the SN95 setup off a V6 or GT car and get the 99+ front calipers and put some decent pads on it.  Use the 93 Cobra MC and Booster and do not forget to gut the proportioning side out of the combination valve and install a manual proportioning valve.  This is how these cars should have come from the factory, period.

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


93 331 Mustang Coupe - 368 rwhp

tc rear 5 lug conversion

Reply #7
So from very recent personal experience...like a few hours ago...the 91-92 Mark VII rotors do NOT fit.  The rotor offset is different.  In this case the hat is taller on the Mark rotors than on the TC rotors.  This puts the rim of the rotor into the bolt side of the caliper brackets.

It's a good thing I didn't sell the 99 GT rear I have from my parts car.  I have a back up to rob parts off of to convert my TC rear to 5 lug.  Why not use the 99 rear?  3.73's...that's why.

tc rear 5 lug conversion

Reply #8
And the '99 rear is 0.75" per side wider than the 94-98 rear ends. So this makes them 1.5" per side wider than a Fox Mustang 8.8. The 99+ rear end housings are 0.75" per side wider than the 86-98 8.8 housings and the axles are 1.5" longer than Fox axles and 0.75" longer than SN95 axles.

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


93 331 Mustang Coupe - 368 rwhp

tc rear 5 lug conversion

Reply #9
hey billy, how much taller would you say the hat is? aero is saying that 99+ axles are 3/4 inch wider than the 94-98, do you think the taller mark vii rotor would offset that 3/4" and line up with the calipers? I dont think I'd go that route cause I dont want my rear wheels pushed out any farther, but I am curious.
1988 Thunderbird sport
2004 Ford F150 Lariat
2008  Chevrolet Cobalt Sport
2007 Suzuki DR-Z400S dual sport/Supermoto
1988 Thunderbird LX - sold
1988 Mercury Cougar XR-7 with GST kit - gone

tc rear 5 lug conversion

Reply #10
Go hear and scroll down a bit and you will see what I am talking about:

https://lmr.com/products/mustang-axle-guide

The 94-98 Mustang rear axle assembly is the same width (give or take a couple 1/16") as the 87-88 TC rear end. This is why they are preferred for a five lug swap in our cars and the parts are readily available everywhere for them.

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


93 331 Mustang Coupe - 368 rwhp