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Metal chips in differential

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I was having a sense of deja vu about this topic and found this thread:

Thread 'Replacement Axles' https://trackmustangsonline.com/threads/replacement-axles.16653/


You're right about the Moser hubs.

On the Strange Axles, they call the removable center the "Drum Brake Register.". Lol. But according to the exploded view in the attached PDF, it is held on by a tiny screw. While there seems to be a lip on the underside of the "register" that fits into the recess on the axle, is that strong enough to shift much load from the wheel studs to the hub?
@blacksheep-1
The center register is solid aluminum held on by I think a 5/16 capscrew. I had trouble initially because one side kept coming loose.
Took it apart cleaned and torqued and it's been good for years.I've been thinking about going with the Strange E-Clip kit.When I installed my watts link a few months ago
I noticed 3 ring gear teeth starting to spall.I'm keeping an eye on it but this next rebuild the C-Clips are history.
 
303
250
Exp. Type
HPDE
Exp. Level
3-5 Years
25 min. to 1½ hrs. from Sonoma (ugh... traffic!)
Torsen for sure. Really helps the car from apex to track out under acceleration. Helps under braking as well since it acts like an open diff under braking, whereas a track lock will still affect handling under braking. I think it is one of the best mods I have done to my cars.

Having said that, I have driven both the 4:1 (FR500S T2R) from my 2006 Mustang GT (3V) and the 2.7:1 in my current 2014 Mustang GT (Track Pack, Boss 302 T2) and can't tell the difference although the 4:1 is "better".

The T2R comes with a warning about hard launches. Frankly, I would recommend the 2.7:1 from the Boss 302 as it was designed for your car and power output.
Thanks for these insightful points
I'm almost ready to pull the trigger on the 2.7:1
I have seen these axles on eBay (2012-2014, 3.73, Torsen) complete anywhere from $1000 to $1200. Haven't looked recenly, but that might be a cheaper option if you haven't already bought your parts.
I briefly considered this option. The unknown state of a used replacement & freight cost vs a new parts rebuild didn't sit well with me. Only reason would be no need to mess with the ring & pinion set-up but I've decided to take this on... I'm actually looking forward to learning.
I've already bought a lot of the parts, no turning back now.
 
6,360
8,180
The center register is solid aluminum held on by I think a 5/16 capscrew. I had trouble initially because one side kept coming loose.
Took it apart cleaned and torqued and it's been good for years.I've been thinking about going with the Strange E-Clip kit.When I installed my watts link a few months ago
I noticed 3 ring gear teeth starting to spall.I'm keeping an eye on it but this next rebuild the C-Clips are history.
Don't do it, most of those C clip eliminators are for drag use only, they don't lubricate the bearings as well on the axles, I don't know of a single one that says it's OK to run them on the street or road course, but if you find different, please post it.
 
179
308
Utah
Thanks for these insightful points
I'm almost ready to pull the trigger on the 2.7:1

I briefly considered this option. The unknown state of a used replacement & freight cost vs a new parts rebuild didn't sit well with me. Only reason would be no need to mess with the ring & pinion set-up but I've decided to take this on... I'm actually looking forward to learning.
I've already bought a lot of the parts, no turning back now.
Cool. Get some gear paint and post the pattern here if you want some feedback before you seal it up. Did you mention if you were putting a new gear set in or a different ratio ring and pinion?
 
6,360
8,180
I finally found a few..

KQjL1SWl.jpg

Mal46yol.jpg

co2Ihjtl.jpg

VYGepJSl.jpg

The top one was old gears, the lower were new Auburn gears in a 7.5.

this is what I meant about polishing the pinion so you can get the bearing back off to change the shim without destroying it, You still want to be able to tap it on with a brass drift, so don't take off too much

86O1CNbl.jpg

6lDD5Z3l.jpg
 
303
250
Exp. Type
HPDE
Exp. Level
3-5 Years
25 min. to 1½ hrs. from Sonoma (ugh... traffic!)
this is what I meant about polishing the pinion so you can get the bearing back off to change the shim without destroying it, You still want to be able to tap it on with a brass drift, so don't take off too much
Thanks for this.
To be clear, this is ok to do to the new pinion? I saw a video where a sacrificial new bearing was used and the inner race was polished to get a similar slip fit. If it saves the cost of an extra bearing and is still a reliable condition I suppose why not. I'm just hesitant to modify new parts
that will be installed.
 
6,360
8,180
Thanks for this.
To be clear, this is ok to do to the new pinion? I saw a video where a sacrificial new bearing was used and the inner race was polished to get a similar slip fit. If it saves the cost of an extra bearing and is still a reliable condition I suppose why not. I'm just hesitant to modify new parts
that will be installed.
I've done it to new pinions, I used to be a big believer in NOT doing it, but after a dragster guy talked me into it, I've done several this way with no issues. Yes, sometimes guys have setup bearings that they use as well. I put the pinion in a lathe ( or drill press) and use Emory paper.
 

Dave_W

Cones - not just for ice cream
984
1,275
Exp. Type
Autocross
Exp. Level
20+ Years
Connecticut
Since you're not getting a whole axle assembly, it doesn't apply, but wanted to document for future readers of this thread.
Some 2013-14 axles (GT500; I think only 2013 Boss possibly only if Torsen-equipped; not sure about PP cars) take a different inner pinion bearing, 6L2Z-4625-AB, which is not in the usual "rear gear install" or diff bearing/seal kits. That's why many of the kits for 2011-14 Mustangs say "not for 2012-13 GT500" - but there are actually more cases of that bearing use so you really need to be careful. Best bet is to use the VIN of the axle's parent vehicle to double check. However, you can buy the standard kit and the other bearing as well, then just swap in where needed.
 
303
250
Exp. Type
HPDE
Exp. Level
3-5 Years
25 min. to 1½ hrs. from Sonoma (ugh... traffic!)
Since you're not getting a whole axle assembly, it doesn't apply, but wanted to document for future readers of this thread.
Some 2013-14 axles (GT500; I think only 2013 Boss possibly only if Torsen-equipped; not sure about PP cars) take a different inner pinion bearing, 6L2Z-4625-AB, which is not in the usual "rear gear install" or diff bearing/seal kits. That's why many of the kits for 2011-14 Mustangs say "not for 2012-13 GT500" - but there are actually more cases of that bearing use so you really need to be careful. Best bet is to use the VIN of the axle's parent vehicle to double check. However, you can buy the standard kit and the other bearing as well, then just swap in where needed.
2014 GT, I ordered this kit, M-4210-B2:


I'm not sure what the "high-torque" bearings are.

Screenshot 2022-05-05 181938.jpg
Screenshot 2022-05-05 181829.jpg

 
179
308
Utah
@DaveW is correct. The Boss 302, Track Pack GT and GT500 come with a larger inner pinion bearing that is not in the kit. I think you will be OK with the standard GT. It is fairly obvious when you get the axle take apart. The Boss 302 bearing is about 1/2 larger in diameter. I picked one up at the dealer for about $35 because I bought the same bearing kit.

I have extra inner pinion bearings that I have hogged the inner bearing surface so I can fit them on the pinion and get the pattern correct with the pinion shims before pressing on the new bearing. Different ways to skin the cat...
 
6,360
8,180
2014 GT, I ordered this kit, M-4210-B2:


I'm not sure what the "high-torque" bearings are.

View attachment 75593
View attachment 75594

Rod is correct,the replacementbearing will fit in the inside/ outside diameters but the race is configured differently for more rollers. They are getting a bit hard to come by these days. But the standard bearing is a drop in, you may have to get them by using the bearing #, not the application
 

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