Converting 1991 SC to use front hubs/spindles out of a 1997 LX

Rick_Leuce

Registered User
Hello,
I read a thread a while ago (cant find it at the moment) listing the benefits of swapping the 1989-1992 Thunderbird spindles for 1993 and newer Thunderbird hubs/spindles. I think they said it didn’t have to come out of a Supercoupe. I would like to upgrade my 1991 SC and I pulled the entire Left and Right front hubs from a 1996/1997 LX (with double piston calipers) and was wondering if there was anything I should or should not do/use when I make the swap. Do I need to buy any adapter kits? Should I just buy Mustang rotors and/or calipers and not re-use the Tbird ones? I’m hoping I can keep using my stock brake booster but I don’t want to cut corners or do anything dangerous. Any advice would be appreciated. :)

Thank you!
 

MadMikeyL

SCCoA Member
I’m a little confused. Did the car you got the parts from already have dual piston calipers on it? If so, then someone already did the PBR brake swap. If not, then you need calipers for a 99-04 Mustang V6 or GT. For some reason, the 99-01 calipers are significantly cheaper than the 02-04 ones. The only difference is the threads for the banjo bolt, but reman’d calipers come with new bolts, so it doesn’t matter. To re-use the stock brake lines, you will have to cut down either the block on the line, or the ridge on the caliper. The hubs for the later spindles are actually different than the early ones, and the rotors are different as well to match the hubs. If the spindles you removed from the 97 have good hubs on them, you can just leave them, but if you have to buy new ones, make sure to get them for a 97. For the rotors, if you want to keep the Tbird bolt pattern, get rotors for a 93-97 Tbird non-sport. I usually just order them for a 95 since there was no sport brake option in 95. The other thing is if you do the PBR swap, you have to grind down the spindle for clearance for the brake caliper. The area to grind is right near where the sway bar link attaches. It will be pretty obvious where you have to grind when you bolt the caliper up. And speaking of sway bar links, those are different for the different spindles as well, so you’ll need a pair of front sway bar links for a 93-97 Tbird.
 

MadMikeyL

SCCoA Member
Yup, those are the PBR calipers, so it was already converted. If you didn’t grab the banjo bolts for the calipers though, then you may wind up having to get reman’d ones anyway, since those bolts can be hard to find. It looks like they never ground down the spindle though, so you can see where the caliper will hit it as the pads wear down. Just pull the caliper off and grind down that area so it clears.
 

Rick_Leuce

Registered User
Hey,
Sorry for the late response, I was furious with myself that I actually grabbed the freaking dual piston calipers I wanted (I had no idea they were dual piston till I got home, I wasn't even planning on saving them) and I dug through all my tool boxes/bags I brought with me to see if I saved them, but I totally left the banjo bolts on the ground besides the car. I may try to go back soon, but not sure if I'll bother this weekend. Is it really hard to buy replacement banjo bolts in this size? Do I have to order a whole new set of dual piston calipers (or pull them) just for the bolts?

It's a 1 hour drive 1-way to get to this place, but if they are that hard to replace and I was lucky enough to get the calipers I wanted, then I guess it's worth the trip.

The 1997 Thunderbird spoiler with brake light in the lower-right corner of the picture was my big "prize" during the trip, so I can't complain too much.
 
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MadMikeyL

SCCoA Member
There are 2 different versions of the PBR calipers; 99-02 and 03/04. One version uses the same thread on the banjo bolts as the stock Tbird calipers, and the other uses a different thread. Unfortunately I forget which version is which, but since you already have those calipers, I would try your stock banjo bolts in them first. If they fit, then you are fine to reuse them, but if not, you will have to track down a set. I know when this mod first came out, the banjo bolts were an issue, but I don’t know if the aftermarket has stepped in and started selling them.
 

Rick_Leuce

Registered User
Thanks for the info. I’ll definitely try out a stock tbird banjo bolt for now and if it doesnt work, I might be able to track down a replacement at an auto parts store. Otherwise I shouldnt have a problem finding those bolts on the ground beside the car. I may go to the junk yard in a month if no easier alternative is available. Worst case-scenario, I know there is a 1999-2004 Mustang at the same junkyard, so I could pull the calipers off of it too.

I still feel like an idiot for actually having the calipers I want in my hand and having no idea. I’ll certainly know better next time.
 

MadMikeyL

SCCoA Member
I would just order a set of reman’d calipers for peace of mind. They are like $35ea on rockauto and you can send those ones back for the cores. Plus reman’d calipers come with new banjo bolts, so that would solve that problem as well.
 

Rick_Leuce

Registered User
I would just order a set of reman’d calipers for peace of mind. They are like $35ea on rockauto and you can send those ones back for the cores. Plus reman’d calipers come with new banjo bolts, so that would solve that problem as well.

Sounds good. I'm not in any rush to do this mod; I just wanted to pick up a couple 1993-newer hubs/spindles in case I ever had the time to convert the front end of my 1991 SC. I'll probably order remanufactured calipers once I have a weekend in mind.
 

Rick_Leuce

Registered User
Good news! I went back to the junkyard, snatched up the banjo bolts I left behind from that Tbird and grabbed the calipers (and banjo bolts) from 2 1999-2004 Mustangs (one was a 2003, I don’t know what the other was, but its PBR Calipers look exactly the same). So I could do the conversion pretty soon. I will wait until I successfully convert my 1991 before I get another set of hubs/spindles for my 1990.
 
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