I was just looking at ARB Air Locker application chart and they now have a front locker listed for the H3. Product number RD51.

Which is the same as the H2. I did not know the H2 and H3 share the same front diff.

 

i didn't know that either. could explain why i'm on my 3rd . . . . . . could also mean that the locker fits both, and probably most, if not all, gm front diffs.

 

Wonder what the life expectancy of an aluminum diff with a locker is?

 

Cast iron w/ front locker would be a set up though!!
How much weight is that stinkin aluminium diff in front really saving anyway??? 5-6#s?? The 3 has Detroit Axels front and rear, will check on what is up front on a 2?

 

When you say Aluminum diff you do mean the housing only, dont you?

As the crown wheel and pinion would have to be cast iron...

 

Yes, the differential carrier to be precise.

 

I wonder about that too. If you put a locker in a cast aluminum housing it will definately strain it beyond it's designed capacity. It's all it can do to holdup to the stock rating of use. The other question I would have is related to the traction control and stabilitrak. How would that affect the systems monitoring of the front drive?

 

Those two systems monitor thru the wheel spindle ABS system, not internally thru the differential.

Brett, here we call the "Crown Wheel" the Ring Gear. Yes, you are right, the gears are hardened steel.

 

Whatdoya think Doc, will it hold up to an Air Locker?

 

In my understanding of the problem, it might.
At first the aluminum diff. was thought to be blowing out because of a defective batch of gears, but that has been ruled out (there were some bad gears, but corrected). It is the little bit of extra flex in the Aluminum vs the cast Iron that seems to be the favored culprit right now. Heavy wheeling can flex the front axle shafts where they meet the carrier, over time this stress can lead to cracking, worn out/cracked bushings, and bearing issues, which in turn can snowball the flex issue??? The carrier should really not suffer too much because of just gear tourque. However, if you have extra gear tourque it mightlead to more riggorous wheeling and bam, problems.

A side note may be interesting to some at this point. I have an 1970 Oldsmobile with a special option rear posi traction differential, the W27, yep, Aluminum Carrier and Cover. The Stock motor conservatively is rated at 500 foot pounds of tourque. The W27 is bullet proof as far as I am concerned, but it obviously doesn't go off road. So that is serious torque, and it holds up w/o any problem?

IMOthe H3 Alum. carrier problemalso may be related to driver error, sometimes they have been tore up on not so tough terraine, because of inexperienced offroaders going too fast, applying excessive power, or not tackling an obsticle in the proper manner. Only one way to find out for sure. Get some people out there with front lockers and see what happens?