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Rear Wheel Bearing Replacement

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Hey guys,

My rear passenger wheel bearing is bad and I was looking at replacing it myself this time. If I'm not mistaken, the bearings were replaced at a shop last time when the seals went bad. While doing some research, I ended up with a couple of questions, hoping you guys can answer!

1. While searching for wheel bearings, I came across these "Repair Bearings". They seem to be a single isolated unit that comes prepacked with grease and seals on both ends of the bearing, isolating it from the gear oil.

Here's a link of the Nationals Repair Bearing, part no. RP-6408

Here's a random vid showing what Repair Bearings look like as a unit.
https://www.youtube.com/watch?v=yStou81OocA

Anyone use one of these before?
I wonder if these would outlast the regular bearings if packed with some quality grease... keeping track use in mind.
Any recommendations on durable bearings?


2. I understand I have to remove the torsen pinion shaft lock bolt and pinion shaft to remove the axles. I'm planing on replacing the lock bolt and the C-clips, as a precaution, because of a tire wall incident I had this year.

I found the following part numbers from the 2011 shop manual, but it's for the clutch pack diffs. Can someone confirm if the part numbers also apply to the torsen diffs?

Pinion shaft lock bolt: 4241
Axle C-clips: 4N237

Link to diff page from 2011 shop manual
 

Grant 302

basic and well known psychic
Pretty sure the Torsen doesn't use the same lock bolt or that type of assembly, as it has three paired sets of helicoil gears.

Not so sure on the C clips at the moment, but I doubt they'd be the same part.

I'm sure somebody has more info on this.
 

steveespo

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Sako
The c clips are the same for all the Mustangs from 1985-2014 and they are cheap so change them. The Torsen lock bolt is a rare item, I haven't found a replacement part # and even contacted Torsen directly but wasn't able to get a response. That bolt should not have a chance to be damaged so I wouldn't worry about it. If it's damaged then likely the whole diff is junk.
As far as the axle bearings I wouldn't use any other bearing than Ford OEM. They work very well as do the seals. Key for seal performance is to properly vent the axle, pressure buildup is what allows the lube to seep past. We run coolers and remote vent cans like the race cars. Car will smell like lube though, you can figure a way to mount it outside with some thought.
Steve
 

ArizonaBOSS

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Easiest thing to do is order FRPP part M-1225-B1 and get the bearing and seal kit in one box.

Here's the information on the locking bolt--I just replaced mine when I did my bearings and seals.

q2qeydU.png

@voodoo child21 @302 Hi Pro @
 
Thanks for the great info guys, really appreciate it!

The parts guys at my local dealer couldnt verify the lock bolt either, but he showed me the exact same one you posted Drew, saying all/most fords use the 4241 lock bolt.

Another question. Do we have any inner axle bearings, or is it just the bearings that are pressed in on the sides of the torsen?

Drew, do you happen to remember the torque spec on the lock bolt?
 

ArizonaBOSS

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F.D. Sako said:
Thanks for the great info guys, really appreciate it!

The parts guys at my local dealer couldnt verify the lock bolt either, but he showed me the exact same one you posted Drew, saying all/most fords use the 4241 lock bolt.

Another question. Do we have any inner axle bearings, or is it just the bearings that are pressed in on the sides of the torsen?

Drew, do you happen to remember the torque spec on the lock bolt?

I believe the "inner bearings" are integral the to Torsen, but not 100% on that.

Torque spec for bolt is 26 ft-lbs according to workshop manual. You might need someone to hold the brake or the axle while you torque that.

Here are the work instructions, btw: http://iihs.net/fsm/?dir=757&viewfile=Rear%20Wheel%20Bearing%20and%20Axle%20Shaft%20Seal.pdf
In lieu of a "bearing installer", you can use the old bearings to help press the new ones in square.

I heated the axle tube evenly at the end with a blowtorch to help get the bearings out, let cool to room temperature. Meanwhile, I had the new bearings in the freezer to shrink them down slightly to help installation. Lube the new bearings with fresh gear oil before install.
 
Thanks for the tips again guys!

I will be replacing both bearings, might as well while the diff is open. Ordered all the tools and the bearing/seal kit. Also picked up the C-clips from the local dealer, will have to go back for the lock bolt sometime later.

Thinking about putting a new set of ARP studs on the axles while at it. Will also be installing a cortex torque arm and whiteline adjustable LCAs... so can't wait to tackle all this!

Steve, after the first time I had a leaking seal, I opened up the axle vent to the atmosphere. I ran a hose to a fuel filter. Since then I haven't had any seal issues.
 
898
544
ArizonaBOSS said:
Easiest thing to do is order FRPP part M-1225-B1 and get the bearing and seal kit in one box.

Here's the information on the locking bolt--I just replaced mine when I did my bearings and seals.

q2qeydU.png

@voodoo child21 @302 Hi Pro @

I have been trying to figure out the pin part number for two years. Thanks Drew.
 
898
544
Sarkis, you do not have to remove the pinion shaft to remove the axles. I agree with everyone else about using OEM parts. If you have questions on how to remove the axles once you get started, give me a call and I can talk you through it.
 
2012-Boss said:
Sarkis, you do not have to remove the pinion shaft to remove the axles. I agree with everyone else about using OEM parts. If you have questions on how to remove the axles once you get started, give me a call and I can talk you through it.

Thanks for the offer, Steve.
I've been watching bunch of videos of replacing the bearings and seals, and it seems like a pretty straight forward job with the right tools. I remember it being simple when Steve helped you replace your seal at summit!
 
If the axle is scoured, I'm assuming I will have to replace the axles.
A quick search online showed some Moser axles, which are more affordable than the OEM ones. Worth "upgrading" or should I stick with Ford axles?
Also read somewhere Moser axles may require different size studs... will have to look into that if it comes to it.
 

steveespo

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Sarkis
I did the Moser axles which are supposed to be a better grade steel than OEM. Studs are the same bore size. The hub center is also shorter than stock so the rear wheels only locate about 1/8" on the hub center. I am going to have some extensions machined to extend out. Also get a set of ABS rings, the originals are not coming off without damage. I heated my new ones to 400 degrees in the oven for 30 minutes and then hammered them on. They are $34 each from Ford. I don't know if the OEM axles already have these on, I don't think so though.
Steve
 
Thanks for the info, Steve!

Based on some research, the Moser axles have stud bores of 0.625" and our studs are 0.614". If the Mosers are really 0.625", then we may be able to use ARP studs 100-7703, which are only $15 for 5, instead of ~$66 for the stock axles!

The contingency budget keeps on increasing!
I hope my axles are in good shape, because I'm going to do the work at a friend's garage. And I dont want to take over his garage for a whole week while I wait for parts to come in, if the axles are bad.
 

ArizonaBOSS

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Agreed w/ @TMSBOSS . If you look closely at the Ford seals, you will see a "gel bead" around the outer circumference of the seal itself, that will fully complete the sealing once the seal is pressed in.
 
Spent this weekend replacing the wheel bearings, seals, and axles with Moser axles.
I had a shop press in the ABS rings onto the axles. I tried heating the rings and cooling the axles, but it was too much banging to be done indoors at night. Pretty sure pissed off a few neighbors ::)

Steve, you weren't kidding when you said the Moser axles dont' have much of a hub!
Once you put the rotors, there's essential no hub for the wheel, so all the forces and stresses are on the studs... I wonder how this will effect stud longevity and reliability on a road course with alot of curbs. This worries me!
Other than that, everything else went smoothly and I've been driving the car ever since. Next up, torque arm.
 
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38
I had the Moser axles in for a year but I always hated the fact that they didn't locate the wheel.
I replaced them with a set of Strange axles.They are about 40% less $ than the Moser,locate the rotor and wheel
and look just as good quality wise.I've been very happy with them.
 

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