Locking rear differential
Laughing Gas
Joined: Dec 2019
Posts: 896
Likes: 256
From: San Diego, CA
I'm assuming the 31 correlates to a 3.73 LSD axle (SRW, Sterling 10.5). I am not sure what the 3E is, but I'm assuming it is the newer 10.5 sterling (2011+).
I am currently running a Ford E-locker from a newer 2011+ Super duty 10.5 in my 2001 rear. The only "mod" is to remove a tang off the speedometer tone ring before bolting it onto the carrier.
I am currently running a Ford E-locker from a newer 2011+ Super duty 10.5 in my 2001 rear. The only "mod" is to remove a tang off the speedometer tone ring before bolting it onto the carrier.
More Turbo
Joined: Dec 2015
Posts: 500
Likes: 38
From: Pacific Northwest
Actually a really good point, I'd look at junk yards for costs on a full axle buy. Then if I could find one, I'd pop it open to inspect that gears are still good, & replace with good synthetic fluid.
Cargo Master
Joined: Feb 2004
Posts: 2,081
Likes: 174
From: Central Texas
It's what I did to change from 3.73's to 4.30's; $400, didn't have calipers, so used my old ones. Make sure the drive flanges are the same, or get the drive shaft end that matches. I also replaced the crappy brake backing plates.
Tuned
Joined: Aug 2018
Posts: 367
Likes: 38
Be aware of a few things if you are considering an axle with a factory e locker (2011+ axle).
1. Rear axles from 2005+ are a different width than the ones used in the pre 2005.
2. 2005+ axles use metric lug nuts whereas pre 2005 use SAE
3. 2011+ axles do not have a VSS in the pumpkin. You will need to add a tone ring to the ring gear and then drill two holes in the pumpkin. One for the VSS and another threaded hole for the retaining bolt.
1. Rear axles from 2005+ are a different width than the ones used in the pre 2005.
2. 2005+ axles use metric lug nuts whereas pre 2005 use SAE
3. 2011+ axles do not have a VSS in the pumpkin. You will need to add a tone ring to the ring gear and then drill two holes in the pumpkin. One for the VSS and another threaded hole for the retaining bolt.
Laughing Gas
Joined: Jan 2017
Posts: 1,221
Likes: 94
Heres the thread how to do it once you price out paying someone to set the backlash etc it make it with it to do the full swap w a 10 year old newer assembly even more so. Also I just bought a new tone ring to make my life easier however I'm sure you can remove the old one. The axle is about 1-2 inches wider my truck has been successfully aligned. As you can see I went to machine shop just because I didn't want to deal with drilling the hole and tapping it. Depending on your experience maybe that's easy for me it would have been the most challenging part of the job. I can confirm this is major update as my 4x4 was not working at the time and use of the e locker saved me in off road situations until able to install a new front driveshaft.
https://www.ford-trucks.com/forums/1...f250-help.html
https://www.ford-trucks.com/forums/1...f250-help.html
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Laughing Gas
Joined: Jan 2017
Posts: 1,221
Likes: 94
Also if your truck is lifted MAYBE the PMF suspension top u bolt plates will let you shift the axle back enough while retaining the factory driveshaft.
https://www.pmfsuspension.com/Adjustable-Alignment-Pin-Ubolt-Top-Plates_p_33.html I am confident that would work however needs firm measurements taken. This also centers your wheels in the well if lifted. If you could use that it would make the update even more worth it for you/your gonna have to swap u bolts anyways as they are single use.
https://www.pmfsuspension.com/Adjustable-Alignment-Pin-Ubolt-Top-Plates_p_33.html I am confident that would work however needs firm measurements taken. This also centers your wheels in the well if lifted. If you could use that it would make the update even more worth it for you/your gonna have to swap u bolts anyways as they are single use.
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Cargo Master
Joined: Nov 2007
Posts: 2,238
Likes: 475
I'd swap the whole axle, used gears can be tricky. I was taught to pattern used gears before you pulled them and then try to match is as closely as possible when you swap them. If it's too far out from how it was, it can cause issues like gear whine, vibrations, accelerated wear and added backlash as they wear into the new setup.
Logistics Pro
Joined: May 2017
Posts: 3,523
Likes: 483
From: Southern OH
Be aware of a few things if you are considering an axle with a factory e locker (2011+ axle).
1. Rear axles from 2005+ are a different width than the ones used in the pre 2005.
2. 2005+ axles use metric lug nuts whereas pre 2005 use SAE
3. 2011+ axles do not have a VSS in the pumpkin. You will need to add a tone ring to the ring gear and then drill two holes in the pumpkin. One for the VSS and another threaded hole for the retaining bolt.
1. Rear axles from 2005+ are a different width than the ones used in the pre 2005.
2. 2005+ axles use metric lug nuts whereas pre 2005 use SAE
3. 2011+ axles do not have a VSS in the pumpkin. You will need to add a tone ring to the ring gear and then drill two holes in the pumpkin. One for the VSS and another threaded hole for the retaining bolt.
Tuned
Joined: Aug 2018
Posts: 367
Likes: 38
My apologies you are correct. I misspoke when I said SAE. They are different lug nuts. The pre 04 trucks I think use 14x2.0 and the later ones use 14x1.5. Or it might be the other way. Either way, they are different.
Tuned
Joined: Aug 2018
Posts: 367
Likes: 38
Heres the thread how to do it once you price out paying someone to set the backlash etc it make it with it to do the full swap w a 10 year old newer assembly even more so. Also I just bought a new tone ring to make my life easier however I'm sure you can remove the old one. The axle is about 1-2 inches wider my truck has been successfully aligned. As you can see I went to machine shop just because I didn't want to deal with drilling the hole and tapping it. Depending on your experience maybe that's easy for me it would have been the most challenging part of the job. I can confirm this is major update as my 4x4 was not working at the time and use of the e locker saved me in off road situations until able to install a new front driveshaft.
https://www.ford-trucks.com/forums/1...f250-help.html
https://www.ford-trucks.com/forums/1...f250-help.html
The VSS was by far the most intimidating and challenging part of this swap for me. I ended up doing it with a buddy of mine. I could have done it myself, but somehow drilling into the housing was pretty scary and he had no issues drilling into it. The thread above provided excellent guidance. Thanks again @RigCity