Thunderbird to Mustang Hub and Brake Swap

 
The to use the MN12 rear rotors you need more than redrilling, the hub bore needs to be machined precisely larger as well, it’s smaller than the Mustang hub center.
 
Okay, looks like I'm getting this done next month and I'm excited as all hell. But I want to make sure I have the little things ready as well.

First: I gather I need 10 of these for the new Mustang front hubs, and that these are the right dimensions:
I'm not sure if there's any particular length of them that would make things easier / harder (there are a lot of variations), or if people have a preferred brand (I see Gorilla mentioned a lot).

Second: Whereas for the rear I need 10 of these:

Third: Spindle nuts. Does anyone have the Ford part number for the OEM nuts? I don't want to mess around with the Dorman ones after all the horror stories I've heard about those, or screw around with a tap. I *think* these are it, but I'm not sure:

Also, how many of these spindle nuts would I need for this?

Fourth: The "MN-12 to SN-95 Bolt Circle Change and Brake Upgrades" article mentions a couple of things that I haven't seen come up.

Even though I'm going with new larger rotors front and back and changing the front calipers, I don't need to change / customize my brake lines at all, correct? Gunn's thread and discussion here hasn't raised this, but the article appears to say that it's necessary.

The article also says you can't get the rear hubs on without a hydraulic press. Is this true? It doesn't seem to be mentioned in other posts, but seems a large stumbling block to doing this yourself.

If there's anything else a beginner is likely to miss in terms of doing this, I'm all ears.
 
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Well I personally haven't done the nub swap but my buddy did and I gave him some tips along the way. The rear you would need to press out and in. But there are hub/bearing puller tools that exist where you can do that work on the car. Though they generally are not cheap. But I think Harbor freight has that type off tool. Or they used to. My buddy for whatever reason bought the Full Tilt Boogie rear hubs, then didn't use them and redrilled the stock hub. So it is possible to redrill the hub on the car.
 
Lugnuts are fine, I used Mcguards on mine and they’ve held up great. Why do you need a arp stud kit for the rears though?

Yeah you need a press for the rear, it’s DIYable up to that point at which you could take the removed spindle new bearings/hub to a shop with one and they could do it for you real quick for a hopefully reasonable fee. That or find a cheap used press on Craigslist or marketplace. When I hub swapped mine way way back I used my friends press, and we both learned the process on the fly so it’s DIYable with the right tools. Keep in mind the torque wrench you need for the spindle nuts needs to go to 250 ft lbs which is on the pricey end of them even for cheap ones, the hub swap is DIY friendly but not budget friendly
 
Why do you need a arp stud kit for the rears though?

I may be misunderstanding, but I thought Gunn's article (first post at the top of this page) says you do. Looking at it again, maybe that's only if you are using Cobra spindles, and if you're sticking with the stock MN12 spindles you only need another 10 of the lugnuts?
 
Gunn replaced his studs because it was a race car. The Mustang hubs use 1/2”x20 studs while the Tbird ones are M12x1.5. The new Mustang front hubs will come with the 1/2x20 studs already pressed in. If you buy the rear hubs from full tilt boogie, they will also have the 1/2”x20 studs, so all you need is 20 1/2”x20 lug nuts, and you are good to go. If you instead redrill your stock rear hubs, you will need to buy 10 Mustang studs, otherwise you will have different thread lug nuts on the front and rear of the car.
 
Yeah, I replaced the studs because one whole axles worth sheared off racing (original 90s Ford metallurgy, two decades of uga-ugas by tire shops followed by several years of lemons races were what killed our studs.

See pics on the old website. I'll find my exact link and update it to point to my own domain later.
 
Thanks guys: that clears that part up.

Can anyone clarify the custom brake line part and how many spindle nuts I'll need? The brake line bit in particular is a concern.
 
You can reuse your stock lines if you wanted, if using PBRs or Cobras you have to grind the banjo block a little bit to clear the passenger side front caliper but they all work fine.

The spindle nuts you need all four since they’re supposed to be one time use. Don’t remember the OE part number unfortunately though
 
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Yep, but it’s only one banjo total you have to grind and it’s quick and easy so if budget is a concern it’s not a bad way to go
 
The rears need to stay stock calipers, due to our parking brake setup. You do need those. Dave's brackets are an easy way to fit cobra disks, ventilated, in the rear, which is as good as the brakes are going to get for less than a few grand. Our rear calipers don't really have a problem locking up the rear, unlike the fronts. If your stock calipers lock up your front wheels easily, you need to buy better tires, lol.
 
Excellent. When this is all over with I'm going to go back and edit in all this detail into the first post and try and make as much of a clear, methodical single-post guide to the process as possible.
 
Wheels- tires front hubs- rear hubs I'd do the lines too. I'm completely ocd tho, lol.
 
What exactly is being pressed, that you need the hydraulic press for in the first place? Is it a part that's being pressed onto the car (in which case the press and the car have to be together) or a part that you can take somewhere to get this pressing done to it, while leaving the car behind?
 
The rear hub bore is pressed into the bearing, and the bearing is pressed into the spindle. Altogether everything attaches to the spindle, which can be removed and taken somewhere to be worked on. The halfshaft splines into the hub and can be removed easily when the retaining nut is removed.
 
Okay, now for the little things. I'm referencing https://www.tccoa.com/d2/members/dlf/Article.html and trying to follow the instructions there. I have questions about the parts list.

1) The "Bearing Retainer".

Bearing RetainerN803955S2

This item isn't actually referenced in the article at all, other than in its part list. According to an Ebay auction they look like this:

Clipboard03.png

Do they go on the fronts or the rears, and what precisely do I do with them? Also, is the Dorman equivalent (933-954) safe to use in this case? (I know it's not for the spindle nuts / retainers.)

2) The Retainers. The article says the fronts and the back require different retainers, but at the same time I've seen reference to what I think are people using the same type for all four retainer nuts (front and back). Which is right?
 
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That’s for the rear in the spindle; you remove it, press out the old bearing, then press on the new bearing and replace the retainer

Front doesn’t use any such thing,
 
Sorry to be pedantic, but the rear, where that is , is the Knuckle. The spindle is the front wheel's pivot. That clip holds the bearing in the knuckle. There's a cast in version on the other side, that you press the bearing in to. Then Put the clip in. Then there's a weather seal. The Wheel hub presses into the bearing center. You must press only on the hub, and support the middle of the bearings , while you press the hub in. The center hub goes in until the wheel flange stops on the bearing. IF the bearing moves away from the retaining feature, so that it's up against that clip, you need to reseat it against the knuckle feature. IIRC, that takes a 3" piece of pipe 12 " long. There's an inside and an outside to the pearing. The inner side fits loose, so you can more easily preload the bearing.Rear preload is 250 lb. front torque is 80-120lbs/ft.
 
Man, the more pedantic the better. Thanks!
 
All the long time guys are pretty ocd types, and one time or another, have had to track down some really random problems. But when we see them now, it's something that's already happened to somebody :)
 
The way the difference was explained to me, the spindle has an axle stub for the front wheel to mount to. The rear knuckle passes the axle thru, to mount the wheel.
 
I always used the terms synonymously since both terms existed before independent rear suspensions were common.
 
As a kid in the 60's. I made the comment to the guys at the garage all the men hung out at, (right beside the bar, and the parts shop, lol.), and was shown by disassembled cars, the difference between them, and the different kinds of brakes, suspensions,shocks vs struts, unibody vs frame, Engine types, everything pretty much.This was 10 years before even motorchcles for me. :) Tommy had a dohc head set for a 429 ford , that wouldn't keep cam towers in place. They don't apparently exist, from looking online:zshrug:

I remember those guys jumping coke bottles with the front tires. These were heavy cars, lol. Of course, they gambled on the outcome. :D

There was a shock tester in theparts store, that demoed the difference in various shocks. One was a bad shock with no damping. I remember more than one young kid tottaly jacking himself, by compressing the bad one with all their weight, and it slipping out of their hand. Positioning of a kid, put you right about chin level, lol.
 
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Okay, I've taken all the information I've gotten here and found elsewhere and edited my original post starting the thread into what I hope is a comprehensive guide with accurate parts in clear English. My hope is that people could just link to this in the future to answer the vast majority of questions on the topic.

Can people review the first post to make sure I'm not missing anything or providing any misinformation?
 
I'l go thru the whole process. A press is really needed, but there are tools that can do it.
Front wheels. PBR calipers, either cobra(17(corrected)"wheels required) or 2004 mustang gt. (Works with 15" wheels.)
2004 mustang gt hubs.14"mustang gt disks
Rear wheels: Dalke's relocation brackets for our calipers, Cobra rotors, Hubs for mustang with irs, New wheel bearing, new seal, 4 new rear hub nuts, quart of new brake fluid,
rear sequence is: press out stock hub. Remove bearing retainer, press out bearing, taking care not to bend the knuckle. Tapping it with a small hammer helps a lot. Press new bearing onto knuckle, replace retainer. Press new hub into bearing, supporting the bearing hub as it goes in. make sure there is grease in the bearing before you put the hub in. I'd do new axles in the back if they have any play. Turn the rear wheel as you tighten it. it will loosen up.keep toruing it to 100 ft lbs, turn, re torque, repeat. Recheck the torque, and when it holds thru a turning session, take it to 250, and rotate more. Recheck. Be sure to recheck torue after you drive it.
 
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I'l go thru the whole process. A press is really needed, but there are tools that can do it.
Front wheels. PBR calipers, either cobra(18"wheels required) or 2004 mustang gt. (Works with 15" wheels.)
2004 mustang gt hubs.14"mustang gt disks
Rear wheels: Dalke's relocation brackets for our calipers, Cobra rotors, Hubs for mustang with irs, New wheel bearing, new seal, 4 new rear hub nuts, quart of new brake fluid,
rear sequence is: press out stock hub. Remove bearing retainer, press out bearing, taking care not to bend the knuckle. Tapping it with a small hammer helps a lot. Press new bearing onto knuckle, replace retainer. Press new hub into bearing, supporting the bearing hub as it goes in. make sure there is grease in the bearing before you put the hub in. I'd do new axles in the back if they have any play. Turn the rear wheel as you tighten it. it will loosen up.keep toruing it to 100 ft lbs, turn, re torque, repeat. Recheck the torque, and when it holds thru a turning session, take it to 250, and rotate more. Recheck.
Minor correction, but it needs clarification; Cobra rotors are 13”, 17s fit. In fact ALL factory produced SVT Cobras with twin piston PBR calipers came with no bigger than 17” wheels. Cobra R is the lone exception to the SN95 Cobras using 18s but it used Brembo calipers, but still only 13” rotors(same as standard Cobra.) funny enough the Cobra Rs “mini” spare wheel is the 1998 17x8 Cobra wheel, as it is the only 8” wide wheel Ford made up to that point that cleared the wider Brembo calipers.

the 14” rotors came in the S197 era along with Brembo calipers
 
I'm still running 15's and 16's, so the cobras are out for me for now. Thanks for clearing that up.
There's still a confusing part, rereading all of it: The stock front disks are also 13", or the front cobra disks are 13"; or is that the rear? I've really lost it now, lol. OK, for my stroke addled brain, What actual size are the mustang disks we are going to use, after the swap, vs the size of the original?
I do have clear that it's the different offset in the disks, that require the relocation brackets. And the rear cobra disk is thicker, and vented.
Man, I just realized, there's a rarer part than a 02 cobra intake. I've actually seen one for sale. I've never seen even a pic of the spare. :)
 

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