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H3 2006 Hummer H3, front differential issues and question regarding 2wd

Mythos_74

Member
Messages
7
Location
Sulphur Bluff, Tx.
As noted in the title this is in regards to a 2006 Hummer H3, it is a 3.5l I5 w/4l60e; I am fairly certain the trim is a Luxury package though not 100%. On to the problem, a damaged front diff bushing was replaced with what was supposed to be the correct aftermarket bushing rather than buy cross-member and all from GM. Couple weeks later the bushing is ripped out of its mount and the front diff is leaking out of the input. After thinking that I have it fixed I am driving in to my town job (25 miles each way) and the front diff goes, I was already planning to try to find a way to convert the H3 to 2wd now if it's possible to do then it's the only choice I have. Now I have rebuilt the transfer case due to needing to replace the nylon/plastic shift fork and a shift detent lever with its tip broken off. I have removed the front driveline as I would with a standard 4x4 with such a problem. All of that said so you know where I am at on this as I am about to lose my town job if I can't get it back on the road again quickly. I can't afford to have someone else do the work plus I have serious trust issues when it comes to my vehicles being worked on by someone else (extremely long story). Here are my questions:
1. How do I disengage the front differential do I have to rework the axels/half shafts and if so how do I do it without pretty much gutting it or is it possible?
2. How do I properly reinstall the encoder motor (I may have it right already but I want to double check it with others who may have had or are currently going through the same or similar experience)
3. After removing the front drive shaft and taking it for a test drive it operates like crap, only positive to it is that it turns better. I am operating it in 4 wheel high lock, though the standerd 4 wheel drive unlocked still will engage which I didn't think possible without a front drive shaft (thus my previous question regarding the encoder motor) The engine spools up way too high before the transmission shifts gears now.
4. Can it be run as a 2wd and what am I missing to get it done properly?

I have spent most of the last 24 years driving a 95 F250 7.3l power stroke. From time to time I would test out other vehicles with a gas engine and up until I got the H3 never found anything I really liked. I had retired my old truck for the most part only useing it when I had a load to pull, now its transmission is out and all I have to rely on is the H3. The H3 is something that I am able to get comfortable in and has room for all the tools I need to carry as well as being suitable for my town job, I am not looking for it to be fast off the line. I do truck and tractor work for the family ranch as well as for others in the area and at night I deliver pizza's for Pizza Hut (laugh all you want, it keeps money coming in and it is the job I am going to lose if I don't get this issue resolved). I can do most work myself I just need to find out what it is that I am overlooking. I have never before bought an awd, I have always gotten a 4x4 to do what I needed in the past. I am certain that I am overlooking or missing something but I am honestly too tired to see where to start (I have been working on this for almost 2 weeks now, getting started around 7 or 8 am and not calling it a night until 1 or 2 am). I can't be throwing money at the problem swapping out parts, I need to get back on the road again asap but everything I have tried so far is fubar. I would be grateful for any assistance y'all could provide.

Steve aka Mythos
 

ski.dive

Well-Known Member
Messages
145
Location
FLORIDA + VERMONT
Some advice=
You said that you deliver pizza with your H3???
The H3 is a terrible vehicle to use for delivering pizza's for Pizza Hut.
I would buy a Toyota Corolla that gets 35-40 MPG for delivering pizza's for Pizza Hut
 

rascole

Well-Known Member
Messages
2,564
Location
Bellflower, CA
Some helpful advice. Removing the front driveshaft will allow you to run in 4Hi Locked for a make shift 2WD. BUT the front diff will still be turning due to front tires do not have unlocking hubs. If the front diff is in fact toast you are at a stand still. There are mixed reviews about removing the CV shafts from the hubs to make a true 2WD but I would NOT do it. You maye have to engage 4HI locked every time you restart the engine.
 

alrock

El Diablo
Staff member
Messages
10,421
Location
Scottsdale
I don't know of any practical way to remove or gut the front diff and still operate the H3. Your best bet may be to look for a junkyard front diff. There are plenty on eBay as well, though that's not really a fast solution.

For the transmission, I'd check your fluid level in the transmission. Did the change in transmission behavior start with the rebuild of the transfer case? If so, is it possible something was not reassembled properly? But I'm curious - how do you know it's in 4 high lock if the encoder motor isn't installed? I know the transfer case can be shifted with pliers or similar (can't recall exactly what people use; cbetts has done this) and reinstall (again, if I recall correctly) is to have transfer case and t-case in the same mode and they should line up and be able to be bolted up.
 

Jeepwalker

Well-Known Member
Messages
853
Location
WI
IDK the true asnwer to your question. But I've owned several full-time vehicles for decades which are full-time and go for 200k mi and beyond. I used to be one of the 'gotta be in 2wd on pavement' guys. But the 4wd part wasn't the issue. On these H3's they seem to have a reputation for being somewhat 'weak' front ends anyway, pavement or not. What you might do is go on the Colorado forums and ask some of the guys there if they have an easy worked-out solution.

Delivery vehicles get beat up pretty quick. It's going to beat your H3 up pretty quick I think.
 

Mythos_74

Member
Messages
7
Location
Sulphur Bluff, Tx.
I am not so much worried about the mpg I get, when it comes to something I spend the majority of my time in for one job or another; my comfort comes first. First 4 years of the delivery gig, I just drove what I did for everything else (95 F250 7.3l ps) due to comfort and familiarity with all its quirks and still managed to make more money than those who lived in town and drove smaller vehicles. Most thought I was crazy until I showed them the actual numbers. You have to keep in mind the safety issues as well, this is not an urban area so a vehicle more suited to the area is necessary to get around. Add in the 50 mile round trip just from the ranch to the restaurant and me being tired and more often than not hurting like hell already and comfort always ranks top, at least for me.
 

alrock

El Diablo
Staff member
Messages
10,421
Location
Scottsdale
With the miles you are putting on daily you could probably rent an economy car and it would come out about even between gas and rental fee. Yeah, it's not as comfortable or as safe as the H3 but it allows you to preserve your job and gives you time to fix the H3. BTW, a junkyard front diff assembly could cost less than rebuilding one.
 

Mythos_74

Member
Messages
7
Location
Sulphur Bluff, Tx.
Yes, the transmission in the H3 not shifting without the engine spooling up past where it should did start after the rebuild. Even being familiar with dealing with transfer case work albeit a different type (think more along the lines of a BW 4407 or BW 3356) I pulled it back out and tore it down after my initial testing and double checked everything and it is by the book. The only variable I can think of is the encoder motor and that is something I am not 100% sure on exactly how to adjust just right on these and as such the thing I keep coming back to. I did reinstall the encoder motor back on the transfer case as per the limited directions in the manual though as I mentioned I am not sure it's right (one of the reasons I question it is that I can shift it to what should be 4 hi unlocked and the H3 will still drive. I was/am fairly certain it should not be able to operate without the front driveline attached unless it is in 4 hi lock or 4 low lock.). I keep hoping that it is just something that I overlooked and someone else who is more familiar with the BW 4494 and/or the electronic shift /encoder motor used will pick up on it. I am hoping my description of the problem is useful, though I am not certain if there's something more I might add that may be more helpful.
 

speedy

Sir Welds a Lot
Messages
345
Location
Dayton NV. Battle Born!!
2wd H3
Simple if your willing to spend a little money or sacrifice your half shafts. This is what i carry on the chance i need to run in 2 wheel drive.
2 old outer cvs that i took apart and cleaned.
Pull half shafts pop them in the unit bearing and tighten
stuff something in the housing ends to keep inside clean
Pull driveline
Drain gear oil.It will spill out of the ends regardless of what you plug the housing with
Switch to 4 high lock
Drive home


cv-joint.jpg
No guarantee but there may be a junk yard option from a gm 1500-3500 Ifs pickup.It uses the same size spline and depth on the outer cv as an H3 The only difference is the physical size of the Cv bell may not clear upper and lower a arms.
Currently set up this way with so we could drive while we waited on front end parts.
 

Mythos_74

Member
Messages
7
Location
Sulphur Bluff, Tx.
I had wondered if something akin to that might be necessary for proper 2wd operation and not just pulling the driveline and putting it in 4 wheel high lock. Still I am stuck on getting the encoder motor and the shift lever shaft issue taken care of, I keep thinking I have it adjusted and install the encoder motor only to have it still not cycle over to the correct setting (or at least it feels like it isn't right when I test drive it). I am stuck at the point where I am about ready to tear down the transfer case again just to check the movement of the shift cam among other things.
 

Happy Hummer

Well-Known Member
Messages
1,294
Location
Wisconsin
Just a thought, have you ripped out the front diff and torn into it yet?
The diff is pretty straight forward. If the housing is cracked that of course would complicate things.
If the seal is leaking at the pinion or case half you can just replace. Getting a cast iron replacement out of another H3 is also an option.
You can get a cross member replacement from several vendors or just the bushings. Lol get the good quality ones tho.
 

Mythos_74

Member
Messages
7
Location
Sulphur Bluff, Tx.
Delivery vehicles get beat up pretty quick. It's going to beat your H3 up pretty quick I think.
That is largely dependent upon the operator (I have watched newbies manage to destroy their vehicles in a couple of months and then wonder why they can't make any money, while spending everything they make on repairs.) and in general I agree. However myself I just don't get in a hurry and don't try to go faster than it's safe to do (often resulting in my turn around times sucking), customers always get their food hot and intact. My old ranch truck did the work for 4 years before I picked up the H3 and started only using the truck for a pull vehicle. I am thinking that with some modifications I should be able to get the H3 to last a long time, at least I am hoping it will. Spend a lot less on fuel now with that 3.5l i5 vs a 7.3l ps.
 

Mythos_74

Member
Messages
7
Location
Sulphur Bluff, Tx.
Thanks to everyone who has responded. I found the problem and now have it resolved, the high/low range shift fork and lockup mode shift forks were not engaging correctly as the shift cam wasn't assembled properly (translate that to mean when I purchased the assembly I did not make sure everything was on the shaft correctly and just dropped it in and started lining it all up. The metal "tab" on the shift cam shaft was to the side rather than in line with its spot on the cam and well y'all already know how that worked for me). So much for my saying that it was by the book. Overall it was like I had thought, something minor I had overlooked due to being too tired to do what I was doing (going between the various jobs I do I should know when I am too tired to keep going) and I now have a few ideas on future projects as well thanks to y'all. I will definitely keep an eye out around here for more ideas on things to work on.

Mythos
 
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