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Torsen install kit

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I have a Torsen T2 from a track pack car and 4.10 gears going into a 2012 GT rear end. Bought the motorsport install kit and did not know there was a specific difference. I did get the upgraded pinion bearing (high torque) but there is something different as we could never get the correct load on the pinion. I started noticing that all of the kits specifically excluded the boss rear (torsen) Note: does not fit 2013 Boss or 2013-2014 GT500 with axle codes S-215-D and S-219-D
So anyone have any input? I'm confused as hell with this. The Torsen in in the track pack is the same as the Boss and so is the housing. Motorsport help line is more confused than I am and that is freaking scary.
 
Just to ask a dumb question up front to get it out of the way, are you using a new crush washer (or a static shim set) to attain pinion preload? Are you using M-4210-A?

Edit - Here is what I found after an Internet deep dive (from SVTPerformance forum user 19COBRA93):
The '13-14 GT500, and 13 Boss with the Torsen, use a larger pinion bearing than all previous GT500's and Mustangs (likely due to a switch to axle housing DR3Z-4010-A). As you can see in the pics above, it's considerably larger and not interchangeable with the others. This bearing was originally used in the 2006-2010 Ford Explorers. It is Ford part number 6L2Z-4625-AB. If you get a 9L3Z-4630-A, it is incorrect for that housing.
In this picture, Top = incorrect 9L3Z-4630-A. Bottom = correct 6L2Z-4625-AB
1612547083206.png

From Tasca:
All GT500s from 2007-2012 used the older style bearing which is included in the M-4210-B2 kit.
The 2007-2012 GT500 and all 2010+ GTs used P/N 9L3Z-4630-A
The 2013-2014 GT500 and 2013 Boss used P/N 6L2Z-4625-AB

Not sure if this is the culprit, since you have a 2012 housing, but thought it was worth sharing.
 
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I have a Torsen T2 from a track pack car and 4.10 gears going into a 2012 GT rear end. Bought the motorsport install kit and did not know there was a specific difference. I did get the upgraded pinion bearing (high torque) but there is something different as we could never get the correct load on the pinion. I started noticing that all of the kits specifically excluded the boss rear (torsen) Note: does not fit 2013 Boss or 2013-2014 GT500 with axle codes S-215-D and S-219-D
So anyone have any input? I'm confused as hell with this. The Torsen in in the track pack is the same as the Boss and so is the housing. Motorsport help line is more confused than I am and that is freaking scary.

Are you using the Ford Perfomance 4.10 gear set? The change in differentials should have no impact on getting the correct pinion bearing preload. I’m also right in the middle of a complete overhaul and trac-lok to Torsen conversion on a 2014 GT axle. With your 2012 housing, the Torsen will go right in with the FP install kit.

Everything I’ve read claims that 200-400 ft lbs of torque is common to get the correct preload, which is a lot. Are you torquing to a specific spec, or are you continuing gradual tightening until the preload is met?

**edited to remove an incorrect assumption on the carrier bearings
 
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So we did get the correct 6L2Z-4625-AB, ordered that separately, and all parts are new OEM Ford and got the big SVT install kit. So the crush washer was new. I actually had the install done by a local guy that is a Mustang specific shop and does pretty much all of the 8.8 gear installs. Initially we though the housing itself was fubar because of the preload and the original 3.73s were screaming like a banshee.
So I bought a completely new (different 2013 housing) to put in the Torsen and gears. (motorsport 4.10).
so to sum up.
1. with this rear I should just use the standard NON-BOSS bearing set?
2. Does this mean the Boss and the GT500 12-14 got a specific differential housing because the bearing itself was a bigger diameter?
 
6,361
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Just to ask a dumb question up front to get it out of the way, are you using a new crush washer (or a static shim set) to attain pinion preload? Are you using M-4210-A?

Edit - Here is what I found after an Internet deep dive (from SVTPerformance forum user 19COBRA93):
The '13-14 GT500, and 13 Boss with the Torsen, use a larger pinion bearing than all previous GT500's and Mustangs (likely due to a switch to axle housing DR3Z-4010-A). As you can see in the pics above, it's considerably larger and not interchangeable with the others. This bearing was originally used in the 2006-2010 Ford Explorers. It is Ford part number 6L2Z-4625-AB. If you get a 9L3Z-4630-A, it is incorrect for that housing.
In this picture, Top = incorrect 9L3Z-4630-A. Bottom = correct 6L2Z-4625-AB
View attachment 62320

From Tasca:
All GT500s from 2007-2012 used the older style bearing which is included in the M-4210-B2 kit.
The 2007-2012 GT500 and all 2010+ GTs used P/N 9L3Z-4630-A
The 2013-2014 GT500 and 2013 Boss used P/N 6L2Z-4625-AB

Not sure if this is the culprit, since you have a 2012 housing, but thought it was worth sharing.
I wrote an article on this somewhere,
 

Dave_W

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I believe I read that the '13-14 GT500 / '13 Boss axle housing is basically no longer available. Someone had their dealer order one under warranty and several months later is was still on national backorder.
 
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Swapped gears in my Trackpack before. This is the parts list I used:

6L2Z*4625*AB Rear Pinion Bearing
3C3Z*4663*AA Shim - Driving Pinion
B7A*4616*A Outer Pinion Bearing Race
B7A*4621*A Inner Pinion Bearing
BR3Z*4676*A Pinion Seal
D5AZ*4670*A Ford Expedition/Lincoln Navigator Rear Oil Slinger
5R3Z*4220*AA Side Bearings x2
M-4216-A300 Gear Ring Bolts


8R3Z*4662*B Spacer / Crush Sleeve

AR3Z*4C121*A Lock nut & crush sleeve


Diff Pin:
D8BZ-4241-C
 
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8,183
That bearing has an OD of 3.543” vs 3.25” for the 9L3Z-4630-A bearing. Not sure how the installer would get that race into a GT housing.
They use a funky outer race, until you see both side by side, then it becomes clear, the Gt500 has more rollers.
You my try this old hot rod trick, install the crush sleeve, slide an .020 pinion shim behind it, and go back after the pre load number. This will force the crush sleeve to crush even more, getting your preload number.
 

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