What’s the DIFF GM? ARB doesn’t know!

1stDeuce

Explorer
I'd second the wait on front diff thing. The brake-traction control in the 2011 GM and Ford HD's is pretty dang good at keeping all fours spinning. Or that was my goal anyway, and I was the traction control calibrator for both those trucks. (Previous job)

Offroad, if you're in High Range, you'll want to disable engine torque reductions with a push of the TC button, or push and hold to get rid of stability control too. When one tire on an axle starts spinning faster than the other, Brake-Traction will come in and squeeze the brake on the spinning tire to apply torque to the opposite tire which has better traction. (You can't shut brake-Traction control off, but it won't keep you from spinning the tires as fast as you want, it'll just try to make sure all four spin at roughly the same speed.) The effect is moderate in high range, but VERY aggressive in low range, particularly in 1st and 2nd gear on the GM trucks, and in 2nd gear on the Fords (Their preference, my judgement on execution...) Brake TC phases out at higher speeds. (15-20mph)

While not as effective as a true locker, if you find yourself in a sticky situation, drop to low range and go easy on the throttle, applying more as the brake pressure on the spinning wheel ramps up. It will cinch down the spinning front tire and the tire with traction will drag the truck if it can. I had the trucks doing cross-ditches uphill with only minimal wheel spin in 1st and 2nd gear low range, so you may be surprised at the capability of your truck even without lockers engaged!

As far as sand goes, I have rarely seen much benefit from lockers on a vehicle with tires aired down to the proper pressures, and without airing down, you'll be lucky to get 10' farther with lockers than without!

YMMV, but likely not by much if I did my job right!
Please no flames... Realize that above all else, the traction control is there to keep you safe when driving on slippery roads, and we had to work within guidelines provided by the manufacturers.

Also, if you run High range in mud and sand, lock it in 1st gear manually. I encountered a lot of conditions where the truck would spin/rev fast enough to do a 1-2 shift, but during the shift the tires stop spinning and when it hits second, it just bogs out. Lock it in 1st and that problem goes away. When you're through whatever you're in, let it into higher gears again!
C
 
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Hi 82fb, 78Bronco, Buliwyf and 1stDeuce: 2011 Chevy LTZ 2500 Duramax 6.6 Allison. 4in Rancho lift, 35X17X12.5 Toyo MT Tires, full size spare, Black on Black truck with a Road Armor winch bumper. X20 waterproof smitybilt 15K winch, shocks and steering stabilizer. Weather Tec floor mats and Supreme H20 Out canvas seat covers. Sweet Truck. Was adding ARB front and rear lockers then got the bad news. ARB is doing the right thing and pulling out the installed rear locker. Lost $200 deposit on camper shell.
I will be 57 years old next month. Now I'm not saying that's too young or too old. I'm just saying the truck I build may be my last. I may never have another opportunity to build another truck. I've lost some time and money and will lose more money in trading in. I don't like losing money.

I hope I never have to use the front locker other than to see if it works occasionally. I've spoke to the engineers with ARB in the US and Australia. With them it starts with a study of the market. I think it took ARB at least 8 years to lock the 11.5 diff. (correct me if I'm wrong please). That's too long to wait and Eaton said they couldn't do it either and didn't even have plans to lock the 11.5. I've been told that a Dana 60 could cost me 10K. If I have to spend another 10K why not get a factory straight axle?

1stDeuce, you put a lot of time into your post. I can't thank you enough. I do appreciate all posts and all are worth considering. TC, I think it has saved lives. It is necessary for daily driving in wet and icy conditions. As far as sand and mud goes the tire that is spinning is counterproductive, digging a hole while the other is trying to get you out. I base my opinion off of this video http://www.youtube.com/watch?v=LFJI0tLMVpI . In sand I may only need to go another 10 feet to find my footing and ill will air down, have a winch, sand anchor, and Maxtrax boards. Sincerely, you really know how to use a modern truck! Please tell me… Will I loose TC, Stability Control, Brake Traction, by installing air lockers or when the lockers disengaged? Your post is going into my truck manual. Thanks again Great Post!
 

Buliwyf

Viking with a Hammer
All your traction control stuff should still work. They won't know a locker is there. A Detroit locker can affect the trucks handling a little, but the ARB should have no effect and acts just like a base model open diff.

Having a front locker may actually be overkill for Texas! I wouldn't sweat it. A solid axle swap would be about $6000. Not a deal killer, but still pricey.

I love ABS. I think ABS systems have to be well built for liability. But I despise regular TC and yaw controls. I'm glad my truck deosn't have it. The traction assist that pumps the brakes to transfer the power to the non spinning wheel is cool, but kinda violent. Putting some serious wear and tear on the driveline and brakes. If it's not the good Bosche stability and traction control that Merc, BMW, and Ferrari use, then I want nothing to do with it.

Then again. I drove a '04 Mustang Mach1 in the snow with Falken RT615R tires (allmost slicks, a type of intermediate tire) with the evil TC turned off and did ok.
 
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