Hello,
I am new to the H3 and this forum. I have been a jeeper for years and have alot of offroad experience. I would like to know if anyone has figured out how to revise the wiring to allow the locker to be used in 4Hlock. Any info would be appreciated.
kk07h3

 

Hello and welcome to the forums. I have the factory locker and do not know of anyone here bringing up this point before. I would have no idea how to change the low only setting and suspect/assume the factory disengage default at 20mph is thru the PCM, so you would also have to do some custom PCM tuning/changes???

This may be easier to accomplish when aftermarket lockers are available for the 3.

 

welcome.......im not sure either

 

Welcome,
Why would you need to lock in 4H?

I've also about 7 years of heavy duty off-roading, and the situations where you have to lock the diff, are when you are in very low speed.

 

I agree with Haim on the low speed aspect, but there are all kinds of different off road terraine and different schools of thought on how to get it done. My locker works great for me just the way it is. I guess we will see what the forum thinks.

 

I've seen this topic visited on several other forums and no one has come up with an answer yet.

As for why you would need to lock the rear end in 4-Hi..........Mud and Sand.

There are instances where your wheel speed/rpm exceed the 20 mph cutoff for the locker
and you are left with open diffs. Sometimes you HAVE to keep those wheels spinning at
a high rate in order to maintain momentum and make it through a pit. Having that locker cut
out when your wheel speed exceeds 20 mph is like loosing a drive wheel. Also, remember
that we are talking wheel speed, not vehicle speed.......In the case of the H3, I would suspect
the 20 mph cutout of the rear locker is to ensure the differentials survival by keeping it out
of extreme operational ranges. I bet if you ask anyone who has traversed any TexasBlack Gumbo
mud or Georgia Clay and they will agree, a locker that doesn't cut out is almost a necessity.

Just my opinion.......

 

Gunner45,I couldn't agree more. I don't have any idea why GM did this but I'm sure it was for some inane reason that had to do with people driving a real 4x4 with NO idea about how they were supposed to be driven. There are times when I would have sold my soul for a front and rear locking diff as I was just barely making forward progress in some sticky, deep mud. My last truck, a 1980 Ford P/U, had front and rear linmited slip diffs and it would wheel circles around most all open diff vehicles in the goo. I have wondered the same thing myself. How could I get the locker to work in 4HI? 3 wheel drive is better that 2 anyday and real four wheel drive is even better. The lame traction control is only so good and is NO substitute for for L/S or locking differentials. I'm sure as time goes on and the Soccer Mommy's and Blingers sell their rigs to those of us who actually use them for their intended purpose, we'll see more and more after market upgrades to improve the H3's traction in the mud.

 

As with any electric mechanical device, the locking mechanism could be overridden with a switch... I havent really looked to see how the locker works. I wonder if it is monitored. You might have to find some way to make the computer think its always disengaged. Probably by unplugging something since there is an option for no locker. Anybody that got a PCM flash...did they ask you if you have the locker?

 

I almost always use 4 lo lock and I can't think of one time I wish I would have stayed in 4 hi and had a locker....

 

In my searching I'm sure I have read somewhere that using a double pole relay they bypassed the factory settings allowing the use of the locker in 2H, 4H and 4L as normal. Using the double pole relay and some trick wiring allows the factory wiring to remain off and the PCM remains clueless.

I try and find it.