Rear Axle Bolt Pattern

[BB767]

I have been purchasing tools and small parts in preparation for my planned Roadster build. Last week I made my first "big" purchase of a wrecked 91 Mustang GT, what I thought from what I have read, was a perfect donor car. It gets dumped off in the driveway and I excitedly get to work on it. What I really need is the rear axle assembly. But wait, what the @%#%$? This thing has four lug nuts holding the wheels on! This does NOT look like the pictures and videos I am seeing from FFV. What gives? I pulled the rear end tag, say's it's a 2.73 limited slip 8.8 inch, that seems right. What did I miss? Shouldn't we have five lug nuts here? Please tell me I have not wasted my money on the first purchase I have made for this car!

[R Thomas]

The recommended donor 89-93 Mustangs have 4 lug wheels the change to 5 occurred with the 94 models. It is common and possible to switch the axles out to 5 lug using Ranger axles. you need to reverse the backing plates for the brakes which requires pulling the axles anyway. you can run the 4 lug most switch to allow a variety of wheels. If you do not already have it getting an electronic copy (9.95 instant download from parts catalog) will prove very helpful.

[AC Bill]

Quite a few 4 lug accessory wheels available for Mustangs still, but if you want the Halibrand style wheels, there is only one place I am aware of that sells them still.

PS Engineering- http://www.psvintagewheels.com/products.html

[GoDadGo]

We've purchased wheels from OEWHEELSLLC and have been happy with their products.
We've got them on my 1995 Corvette, my son's 2000 Camaro and our current project "The GoDadGo Chevy Cobra!"
I can't complain about the quality one bit, plus their prices have always been very reasonable.

http://www.oewheelsllc.com/Wheel-Sin...tang/year/1991
http://www.oewheelsllc.com/Wheel-Sin...tang/year/2000

You can check out our wheels on the attached video links:

https://youtu.be/svZX2BMSDEs
https://youtu.be/_wnHDNgnNqs

[KegMechanic]

I changed mine using these https://www.summitracing.com/parts/sum-700122
It's a straightforward swap. Lots of youtube videos out there if you need help.

If you're using the Mustang front components order front rotors for a ’91 Lincoln Mark VII. They are a 5 lug lug direct replacement for the Mustang rotors.

Like R Thomas said, I purchased the download version of the build manual before I started anything. It has been a great resource.

[Jeff Kleiner]

... Shouldn't we have five lug nuts here? Please tell me I have not wasted my money on the first purchase I have made for this car!

"Wasted"?---not necessarilly. Not done spending $$?--- maybe. Kind of depends on what your end goal is. There aren't a lot of straight up Fox body donor builds being done in recent years but that doesn't mean that there is anything fundamentally wrong with that approach. Yes, you can use the 4 lug axles, drums and rotors along with original Mustang or aftermarket wheels if you like. Just because it is not commonly done doesn't mean that you shouldn't if your budget or final vision dictates. Same with things like the 2.73 axle ratio, control arms, 4 link rear, etc. A couple of the nicest and most impressive builds I've seen over the years have been strictly donor based. You can build a basic car and in the end have as much fun as the guy parked next to ya' who spent 3 times what you did. Where do you want to end up?

Good luck,
Jeff

[BB767]

Hey, thanks for all the comments. You have made me feel a little better. I see I did not mess up but it was not mentioned that I would have to re-axle the donor rear end! Anyway, I plan on getting a full kit, have already downloaded the e-version of the build manual, again, no mention of new axles. Plan on getting the 11" FFV discs on the rear. Definitely want the Halibrands, 17". Since someone brought it up, what rear axle ratio should I end up with? I am leaning towards 3.27. Would like a little taller gears but do not want to drag the clutch every start either. Plan on getting a 351W 427 FI around 500 HP M/L with a TKO 600. R Thomas, thank you for the facts, they confirm I did not screw up. Keg, thanks for the Summit part numbers, have been trolling their offerings but was not sure which ones were right. Jeff, as you can see I am planning on a full build, just do not like surprises. Where do I want to end up? With a well built, well set up car that has more power than most people need, just like the rest of you out there!

[Big Blocker]

Well said Jeff . . .

BB767
FWIW

I have a friend who built an early MK I as a complete donor build way back in the day . . . the car was flawless and perfect in every detail. It did have the four lug Halibrand style rims in 15" that were available back then - might still be available from PS Engineering. I'd give them a call if you want to stay within your "donor" budget.
Guys on this (and the other forum) will be happy to help you spend your money . . .

Doc

[AC Bill]

I see I did not mess up but it was not mentioned that I would have to re-axle the donor rear end! Anyway, I plan on getting a full kit, have already downloaded the e-version of the build manual, again, no mention of new axles.!

The original pretense of FFR kits, was to be able to use a wide range of donor years, some have 4 lugs, others 5 lug, some have rear calipers, others drum. I guess they couldn't know what a builder may end up with, so they just don't cover that aspect.
In the back of my MK 3 manual, there is mention of different length axles, that could affect the tire size and wheel backspacing, so the variance was recognized, they just didn't get into the lug numbers.