What’s the DIFF GM? ARB doesn’t know!

[JustinFeaverhead]

So I’m trying to build a trustworthy 4 wheel drive with Selectable Lockers in the front and back. Have a 2011 Silverado 2500 HD LML LTZ Duramax. Last 8 on VIN: BF192149. I choose ARB lockers for their reputation and because they could provide lockers for Front and Back Diff’s and because Eaton claimed to have front lockers but had no intention of developing a selectable rear locker. 4 wheel Parts is my builder. I spoke to ARB before ordering and it was confirmed they had the product to deliver my desire for lockers. The rear lockers were installed and when the front were being installed it was not possible up to this point. 4Wheel looked for support and ARB support said this: “Our engineers have never seen one of these and we’re trying to figure out exactly what GM did here.” They are at a loss right now, but they did say they are “not sure how their locker would work with that type of diff because the air collar that engages the locker works off of the side bearings.” Now ARB claims they will update their website to inform others with my same intentions and they also claim that they have installed front lockers on 2011 Silverado 2500 HD’s before. It would help me to decide on how to proceed if I too knew what GM has done to the front differential on this truck. Can anyone help to explain this deferential.

http://imageshack.us/photo/my-images/37/004ral.jpg
http://imageshack.us/photo/my-images/268/007kbt.jpg
http://imageshack.us/photo/my-images/651/001dfg.jpg
http://imageshack.us/photo/my-images/839/003nrj.jpg
http://imageshack.us/photo/my-images/528/006em.jpg

 

[FellowTraveler]

Your front diff OPTION

Perhaps, going to an earlier version GM IFS 9.25" will be a better option they have proven to be strong too, if I remember right ARB's front air locker for this also fits some Dodge front diffs.

Good luck!

 

[gmcpimpin]

I did a little digging and it appears that went too this style AAM differential in 2011 when they redesigned the heavy duty trucks.

http://www.fourwheeler.com/techarti..._for_the_2011_gmc_and_chevy_2500hd/index.html

 

[JustinFeaverhead]

Thanks FellowTraveler & gmcimpin, It apears to be either go to another year Diff or another truck. Spoke to Eaton and after they had a chance to see the photos now they say they cannot do it either. Eaton said no one can. So now the question is can I get a 2010 diff into the truck after the new style changes?

 

[FellowTraveler]

Convert

After examining the pumpkin photos you have I'm thinking a conversion to an earlier frt/ifs/diff can be done keeping in mind you would need the earlier cv shafts maybe hubs too unless splines are the same. The earlier K2500/3500 ifs/diff is very stout and many aftermarket options exist for it.

 

[82fb]

Is there some reason you couldn't wait a few months or year until ARB has one available for the new style?

 

[JustinFeaverhead]

@82fb, The 11.5 came out in 2001 I think? ARB came out with the locker, what? 2010.? Hearsay.... but a long time if it's true.

Thanks FellowTraveler, I'm going to ask Chevy dealer to look at that angle.

 

[FellowTraveler]

@82fb, The 11.5 came out in 2001 I think? ARB came out with the locker, what? 2010.? Hearsay.... but a long time if it's true.

Thanks FellowTraveler, I'm going to ask Chevy dealer to look at that angle.

I had installed the ARB locker in my Burb long ago it was the first series and when ARB updated the unit I received updated parts free. Good product and service.

IMHO, you have a great truck already and will only make it better with diff mod. The dealer will be pricey if that is what you want fine, however, good low mileage earlier 9.25" diffs can be had on e-bay for $350. (I just bought a spare, yep, even a spare t-case), rebuild it if it makes you feel better, mounting tabs can be fabricated if different, axle shafts can be made too to match up to hub spline if different.

On a full sized heavy vehicle a front locker is about the greatest mod ever for that extra traction when needed.

 

[JustinFeaverhead]

Thanks FellowTraveler, The dealer will only do bolt on replacements for cutting and welding I am going to need to find a hard core off-road shop. I don't think 4wheel parts is up to it either.

 

[JustinFeaverhead]

Looking for a good hard core off-road fabiraction shop in the Houston Tx area? Any recommendation?

 

[herm]

hello from gm-trucks.com! i saw your thread over there.

 

[JustinFeaverhead]

They say it's not the destination but the journey. This journey is not so nice knowing that some good things come at a price. I love the truck, it's the best one I ever had. But my goal was to build a full size truck with selectable lockers and if ARB would have not told me it could be done I doubt I would have purchased it. It's a beautiful truck but just a tool to me. I want all of the advantages I can afford to get me in and out of a beach that is 60 miles long and there is only one way in and one way out. The way out is the same as you go in. Weather can change quickly here in Texas. So I'm looking on how to salvage my situation.

Hi herm, going to trade her in for a Dodge. I hate to do it but like I said It's just a tool! Havent had a Dodge since my Dart with a 440 in it, and push botton shift. Wow takes me waaaaaaaaaay back. Thank You all for replying.

 

[82fb]

Hi herm, going to trade her in for a Dodge. I hate to do it but like I said It's just a tool! Havent had a Dodge since my Dart with a 440 in it, and push botton shift. Wow takes me waaaaaaaaaay back. Thank You all for replying.

Of all the reasons to trade in a vehicle this one is close to the wierdest. But to each his own! Either way, you are going to end up with a sweet truck...

 

[78Bronco]

SAS?

 

[Buliwyf]

I'd just wait.

We hardly ever use front lockers anyways. By the time you actually need to switch one on, there will most likely already be a ARB or OX locker out for the front of your truck. Just put the rear in now.

Or swap in a Dana 60 SA! LOLz.