Confirmation, Gear swap and rear diff

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Maz762

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Thanks in advance for any knowledge you guys can pass to me. I've got a 2012 1500 Express, leveled on toyo 33 at tires. Came with 3.55s and an open rear diff. I had no vehicle waiting so I bought it sight unseen coming home from my last deployment. Didn't check the build sheet so I have no one to blame but myself, if I'd known about the zf235 I would have kept looking. I want to go to 6 inch lift on 35s but won't unless I can get atleast 3.92s and a lsd, preferably a locker. Who out here has managed a gear swap and a locker or trutrac? Heard I can fit a stock lsd, but that's it. Any way to do it short of a full axle swap and front diff housing? From what I've picked up on this forum the front ring gear is welded in and the zf235 shafts are different lengths. I love the truck and don't pull anything more than a 18' boat, but if this doesn't work I'm moving up to a 2500.
 

jlb

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235mm = 9.25in

The rear ends are not 8.25in, otherwise this would be a pretty nice option. The stock LSD is a *************, just FYI.
 
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Maz762

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Heard the stock units aren't worth the trouble. Looking like I'm out of luck with this truck. Anyone know what year rear axle and front diff housing I could use? 09-10 or can I use them off a 3rd gen? Must be someone here in the same boat as me.
 

DannyMK2

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you would need the rear diff out of an 09-10. cant use a third gen axle as they are leaf spring, unless you want to make even more work for yourself. front diff i believe changed in 2012 meaning you would need an 09-11 set up but i am not 100% sure about that. it could be 09-10 like the rear. however, going through all that work only for 3.92's seems excessive. i would go 4.56's at that point.
 
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BlkRamRt

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Heard the stock units aren't worth the trouble. Looking like I'm out of luck with this truck. Anyone know what year rear axle and front diff housing I could use? 09-10 or can I use them off a 3rd gen? Must be someone here in the same boat as me.

Not worth it in what way??? There is members on here that have done factory lsd and grear swaps on here they have zero issues. There is also guys here that are boosted that are running factory gears and no problems. The only problem with the 4th gen RAM's is the 6 speed transmission.
 

O.R.T.

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235mm = 9.25in

The rear ends are not 8.25in, otherwise this would be a pretty nice option. The stock LSD is a *************, just FYI.

No, I got that part, I was looking for something I'd heard about. It may have only been a rumor last November and may possibly show up this November. (SEMA)

**I'd have to verify the application(s) below are for 2011-Current.**

I know there's a lock-right (lunchbox locker) but I don't trust lunchboxes. 12bolt/31spline required. http://www.spiderautomotive.com/lockright1220.html

There's also supposed to be a Detroit TrueTrac conversion available. Again, 31 spline requisite.
These show on my side, they should be on 4wp's website. Tor-sen style.
images.ashx

images.ashx


Yukon also apparently came out with one.
yga-26019.jpg
 
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Maz762

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Where did you hear about a Truetrac conversion. Either that or a detroit locker would be perfect. Found this NEW Chrysler 9.25 How does this rate against OEM?
 

DavidRam

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Auburn Gear First to Offer Aftermarket Alternative for Post-2010 Chrysler 9-¼ ZF Limited-Slip Differential

Auburn’s new 9-¼ limited-slip differential broadens consumer choice and delivers superior strength and performance for about 25 percent less than OE diff. AUBURN, Ind., Aug. 19, 2014—Auburn Gear, Inc., a leading U.S.-based manufacturer of high performance differentials, introduced its new aftermarket, limited-slip differential replacement for vehicles with the Chrysler 9-¼ ZF rear axle built after 2010. Auburn’s new aftermarket 9-¼ differential is the first to market and is designed for easy installation and higher performance than the original equipment.

Until now, those wanting a limited-slip differential on certain Dodge, Jeep and RAM vehicles made after 2010 had to either specify it as an option in place of the standard Chrysler 9-¼ ZF open differential or pay to have an OE 9-¼ ZF limited-slip retrofit performed. Cost was often a barrier, and the OE-made posi-track was the only aftermarket option available. “Folks would call me and ask about retrofitting their trucks, but once I quoted them a price for the OE replacement, they’d often change their minds,” Ron Hill, sales manager for Pyle Bros. of Baytown, Texas, said. “We’ve always been impressed with both the quality and operational characteristics of Auburn’s differentials, and their new 9-¼ gives me a lower-cost, higher performance alternative for my customers.”

Auburn’s new high-torque-bias limited-slip differential is engineered to surpass the abilities of the OE differential, making Auburn’s new differential even more attractive to those who want to upgrade their drivetrains and their performance capabilities. Auburn’s design provides superior bias torque to the high-traction wheel and is compatible with gear ratios of 2.71:1 and up. Aggressive off-road driving over difficult terrain can challenge some differentials to the breaking point. Auburn’s new 9-¼ limited-slip differential is designed to stand up to significant punishment and gives drivers smooth torque-sensing operation with correct bias ratios
engineered to outperform other standard differentials.

“I expect Auburn’s new diff. to be stronger overall and to deliver better traction, so we’ll see less one-wheel wonders,” Jeremy Ayers, president of J.T.’s Parts & Accessories of Cashmere, Washington, said. “Auburn’s products have the best warranty in the business, and the fact that their products are made in the U.S.A. is important to our customer base.” Auburn Gear has been manufacturing its products in Auburn, Indiana, since 1982. The company
engineers a wide variety of performance-enhancing and high-performance aftermarket differentials and believes that being exclusively American Made is one of its unique advantages.

All Auburn differentials are backed by the company’s one-year warranty and exclusive Differential Replacement Exchange (D-REX) Program. According to the terms of the D-REX Program, Auburn will replace any differential within the first four years of purchase, regardless of circumstances. The replacement differential is one-third of the original cost (that is roughly the equivalent of the price of a competitor’s clutch pack). The replacement differential comes fully assembled, tested, certified and ready for installation. No rebuilding is required, and thus no mixing of old or worn parts with new parts is necessary. “We watch the market closely, and we saw the need for a competitively priced aftermarket 9-¼ limited-slip differential,” Jamie Forrest, senior product engineer for Auburn Gear, said. “I’m excited to say that we brought our solution to fruition within 9 months of its inception, and it’s the extra effort involved that has allowed us to be first to market with our aftermarket 9-¼ solution.”

Auburn’s 9-¼ limited-slip differential, model number 5420142, is expected to begin shipping on or about Sept. 30, 2014. Auburn’s new aftermarket differential can be used to replace the open case or limited-slip differentials on Chrysler 9.25 in. ZF axle models.
 

SILVER_BULLET

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so just wondering will that work with 4.56 gears? i read what you posted but im not sure if i missed that part or it didnt say it
 
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Maz762

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Ordered the auburn lsd. Going to have to live with the gearing for now. Time to pick a lift kit.
 

O.R.T.

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^That's the company! Knew it began with an "A" so I'd automatically thought "ARB" at first.

I have friends who use Auburns in their crawlers. Good Stuff.

Post all you can get in this thread. Take a lot of pictures, from delivery of the box, thru install, to some trial runs so the rest of us can reference it.
 

DavidRam

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^That's the company! Knew it began with an "A" so I'd automatically thought "ARB" at first.

I have friends who use Auburns in their crawlers. Good Stuff.

Post all you can get in this thread. Take a lot of pictures, from delivery of the box, thru install, to some trial runs so the rest of us can reference it.

^^^ Yes please!
 

fasthemiram12

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IIRC your still limited to the factory 4.10's
 
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