2008 Hummer H3 Alpha

[JPaul]

And here is the latest repair I discovered I need to do. While messing around with the A pillar trim and snorkel bracket, I noticed my roof channel trim was looking in bad shape so I decided to take it off and see what was up. When I did that I discovered that the weld seam was covered with some type of "sealant" (quotes because it's apparently actually fairly porous and good for nothing but helping the metal rust) that was starting to bulge up and crack in several places. A bit of picking with a screwdriver and...

Thanks a lot GM. I know I've seen earlier model H3's roofs that did not have this stuff on it. Maybe they started adding it in 2008? At any rate, it is crumbly and chips right off no problem. Almost seems like a type of dense celled foam? Looks like it should only be used for interior applications though. All it seems to do is hold the water in and help everything rust. The good news is that it is super easy to take off. The bad news is this is yet one more thing to deal with. My plan is to strip it all off, clean off the rust, prime and paint it, then seal it with some high quality urethane roof sealant. Probably something like what is used on RV's.

That of course was not the cause for the roof channel trim being wonky, it's just getting old and warped is all. I'll eventually replace them but they're over $200 a side, mainly because they include the U channel for the roof rails.

 

[JPaul]

Well, it has been a while since I updated this. Life has been keeping me pretty busy this year between my job and the new house/property. All these people claiming to have tons of free time due to COVID seem a bit farfetched, I've never been busier.

Let's see, where was I? Oh yes, I had finally settled on using the ARB locker activation compressor for operating the lockers rather than the ARB twin, fixed the battery tray setup, and fixed one side of the roof weld seam. Still need to fix the other side.

A little bit after getting the compressor installed I ended up messing around with the winch control box and wiring. I had it on top of the winch for a while but didn't like it being right there, plus it was rubbing on the bottom of the grill, and the goofy mounting clips were coming loose due to the screws backing out. I ended up moving the winch controller connector to another side of the box so that I could mount the control box right behind the passenger bumper pod. Turned out pretty well and it has opened up the top of the winch and improved the airflow to the radiator a bit.

The old spot was on the left of this shot. I plugged it up with some aluminum and sealant.

New spot puts it between the wires to the winch.

I had to drill new holes for the mounting screws to tighten it up a bit due to the orientation I had to go with to make it fit between the cables.

Mounted behind the bumper pod.

It's a little tight getting to it, and I actually had forgotten where I had even put it when I had to use my winch in November to get myself turned around on a snowing mountain road while Christmas tree cutting, but it works well for me.

 

[JPaul]

Skipping over the rest of spring, all of summer, and into fall (which all of that was spent working too many hours at my job, fixing up a ton of stuff around the new property and house such as sprinklers, windows, etc, also getting a 1/4 acre garden planted and tended to, more work, some vacation time with my family to South Dakota and a camping trip in the Uintah's here in Utah, more work, the elections, taking my oldest daughter shooting for the first time, and tons of other stuff), I finally started turning my attention back to the H3 a bit. Mainly because the blower fan stopped working again. Took me hours to run through all the troubleshooting I did last time this happened just to finally remember I had already figured out the problem and simply never got around to fixing it.

This connector has a bad connection in it for the power to the blower fan. Possibly due to being used as a tap to run several other medium draw circuits by a previous owner. At any rate, I wasn't about to try fixing the connector itself. Took a couple pictures of the connector and wire to remind myself of the repair that needed to be done, which wouldn't happen until a month later with the connection finally going out often enough that I got sick of trying to kick the wiring harness while driving to get the fan back on so that I wouldn't freeze while driving.

Here is the trouble child. It's the brown wire that is wrapped with self-vulcanizing rubber wrap to cover the spot a suitcase tap was added to feed the extra circuits that were added.

And here is the fix. I simply cut the wire on either side of the connector, stripped it, and added a splice in with some crimps. Sounds a lot easier than it actually was. I ended up having to take the lower panel off the dash and even then it took a bit of cursing and several attempts and questioning my life before I finally got them crimps done. Problem is permanently solved though. I highly doubt I will ever need to take this apart, and if I do I can just cut out one of the crimps and add some spade connectors instead or something.

 

[JPaul]

In between the end of October when I had to recall the issue with the body harness connector and the blower fan and the end of November when I actually fixed it finally, I ended up buying a 16' 6k lbs car hauler trailer to use for, well, anything really. I needed a trailer to be able to transport my riding mower and leaf sweeper and cart and whatnot over to my in-laws on the other side of the valley to help them clean up their yard from leaves a couple times. My father in law is getting up there and he has prostate cancer that is limiting his ability to get much done so I am glad I am able to help them out. Plus it gave me an excuse to get a trailer.

I ended up going with the car hauler since it was the max weight my H3 can tow (6k pounds) and would give me the most flexibility. I don't have a truck and this being 16' will allow me to haul pretty much any building material I could need and even small vehicles and other heavy-ish items. I am going to build sides for it and may even build a fold down ramp for it to make loading and unloading my riding mower and ATV's more readily. I'd like to also add a winch to it for pulling vehicles and such up onto the trailer. I'll probably upgrade the winch on the H3 and put the Badlands 12K winch from the H3 onto the trailer.

Eventually I want to get a 10K car hauler to use for heavier items, particularly my H3 for rock crawling trips. But I need to get a truck that can pull a 10K trailer first, according to my wife anyway. So this will do for now.

 

[JPaul]

This now brings me to the last couple weeks. I finally had some time off of work and since I got a good sized bonus this years (surprisingly) I was able to afford to finally get new tires for the H3. I've been running the same set of 33" Duratracs since my first H3 clear back in 2014. 6 years on a set of tires and I'm not sure anymore how many tens of thousands of miles is pretty good, but the Duratracs are definitely done for. 2 years ago in Moab I noticed I was slipping in areas I had never had issues before, and this winter when I went to go Christmas tree cutting they did pretty badly really.

After much hand wringing, googling, debating, and soul searching, I finally chose a replacement. While the Duratracs are great tires and great in the winter, especially when new, they just aren't as tough as I would like for the types of trips I want to be able to start doing. Now that I don't have to drive it every day (I have my wife's old Charger to use for commuting now) I can afford to have it become more purpose driven for off-roading. So not only did I decide to go with a different model tire, I also decided to bump up to 35" tires. I settled on 315/75R16 General Tire Grabber X3's. I really wanted to try the Firestone MT2's, but there is so little information out there about them that I had a really hard time being able to go with them. The Grabber X3's on the other hand supposedly do really well in the winter for a MT, and they have a lot of good reviews overall. Of course though no one had any in stock up here in way northern Utah, and no one could even order any. I ended up having to go through Discount Tire down in Ogden and they had to have them shipped out from Georgia.

So, no pictures of them yet, they just barely arrived to the store this morning, and while I would have gone down today to get them installed, what I ran into after ordering them has put a damper on that hope unfortunately.

Since I was getting new tires, and finally had the time to work on this, I decided I was finally going to finish hooking up my ARB lockers to the compressor. I wasn't in any kind of hurry before since all my trips ended up being cancelled due to the pandemic, and I figured it would be fine since the bulkheads on both axles were plugged with a short piece of line that was folded over.

First, onto the good part of this story.

I chose to run hardline along the frame rail and only use the nylon tubing ARB provided between the differentials and the hardlines, and between the solenoid valves and the hardlines. This way the tubing wouldn't be too much of a concern since the hardline would hold up best to any hazards underneath, including high heat from the exhaust.

I used 3/16" copper-nickel brake line along with compression fittings and female/female fittings to be the main runs. I ran the line for the rear along the passenger frame rail (the driver frame rail is inaccessible in the rear due to the fuel tank and I wasn't about the drop that) and up the firewall using retaining tabs screwed to the frame and the firewall to hold it all in place. I routed it across a rear crossmember to be just over where the bulkhead fitting on the diff housing was. I used some boiling water to help form the nylon line into a 90 degree angle and left a couple loops of line to allow for the travel of the diff.

For the front locker I only had to run a short bit of hardline along the frame rail and up the firewall. This spot is where I was worried about heat damaging the nylon tubing since the cat is right there.

Then both lines come out at the top of the firewall and are connected to the solenoids via the nylon tubing.

While working out all the fittings, I discovered two problems. First, the female/female couplers I purchased off Amazon turned out to not be 1/8 NPT, but rather 1/8 BSPP. For those of you that are either not from outside the US or aren't familiar with BSPP, that stands for British Standard Parallel Pipe. Which not only is not tapered like NPT, but it is also a slightly different thread pitch, 28 TPI instead of 27 TPI. I had no idea this was a thing, but it turns out a lot of the fittings you get from China tend to be BSPP or BSPT (British Standard Pipe Tapered), rather than NPT. Hence reviews that complain about them either not fitting at all or fitting loosely, depending on which way you're going with fittings. On top of that the 6mm push connect fittings I had purchased were 1/8 BSPT. So while they would fit OK into the 1/8 BSPP female couplers, the 1/8" NPT 3/16" compression fittings I had purchased didn't go in AT ALL. So my idea was to get a 1/8-27 NPT tap and die and make adjustments that way. It worked, sort of. Turns out my fear of the coupler cracking came to reality on at least one of the connections. So I ordered some proper 1/8-27 NPT couplers and also ordered the ARB 6mm push connect fittings since it turns out there is a "universal" type that works with NPT, BSPP, and BSPT, mainly due to having special threads and an o-ring to provide the actual sealing. Once those all come in I will redo the connections to get them setup proper and leak-free.

For now I have wired the compressor and the solenoids to my SwitchPros SP9100. I did just order an extension cable for the ARB harness though so that I can run that into the cabin and use the spot the old rocker switches were for the electric lockers. $14 for a premade harness vs me spending time splicing the existing harness to be longer is worth it to me.

After getting everything hooked up I jacked up the front of the truck and tested the front locker. Success!

Sadly, this is where the good part of the story ends...

 

[JPaul]

When I went to the rear and jacked it up to test the rear locker, to my dismay it would not engage. Granted, it has been a year and a half since the locker was installed so I thought maybe it was just a little stuck or something.

To spare you all the gory details, I'll summarize. I checked the airline, air was getting to the locker just fine. Took it for a drive to warm the diff up (it's been below freezing here for a while and has been getting down into the teens or lower at night). No dice. Hooked my pancake compressor up to the locker directly (the push connect fitting screws into the end of an air gun decently enough) and started going from 90 psi to 110, 120, all the way up to 150 psi in case it needed a shove. Still nothing. Not hearing any air leaks inside the diff.

Ended up taking the cover off. Still nothing. Locking sleeve isn't moving a micron. No air leaks. Now I will mention that when I pulled the bit of line out that was acting as a plug for the push connect fitting on the bulkhead fitting I noticed that it was pretty dirty and the end was not cut square but instead at an almost 45 degree angle. I was concerned about this but hoped that it had still sealed up.

But by this point I was starting to realize that might not have been the case. I unscrewed the push connect fitting from the bulkhead fitting and then found this sight:

I wasn't totally sure what I was looking at when I took that photo, but I would figure it out soon enough. I undid the bulkhead fitting and discovered that the jam nut (which turns out to be steel) used to seal the copper line inside the bulkhead fitting was rusted. That means that water had gotten inside. Great. If water got in then that means dirt had likely gotten in as well. So it was possible the copper line inside the housing that goes to the seal housing on the carrier was plugged. Since it was in a U shape (the installer had left most of the copper line inside) I was hoping that it would have acted like a trap and kept all the water and junk in the U bend and not made it's way to the seal housing. I cut the copper line close to the seal housing (I could always splice it back together) and cleared out the cut off portion. Sure enough gunk came out, but also diff oil. That had me hopeful, but it was misplaced hope. I hooked the bulkhead fitting directly to the now shortened copper line to the locker and tried the shop air again. Still nothing. I ran a piece of wire inside the line and measured to see if it was plugged, it didn't appear to be. I thought maybe it was the locking sleeve was seized for some reason so I sprayed it with carb cleaner first and then a bunch of PB Blaster. Still nothing. Heated it all up good and hot with a heat gun. Still nothing. Left it overnight and tried again the next day. Nope.

Crud. The only thing left to do was to pull the carrier out and disassemble it to figure out why exactly it wasn't working. I did that but noticed when I loosened the bearing caps the carrier was loose enough to come right out, no pulling or prying needed! That seemed wrong. Everything I had read was that you'd need to pry it out due to the amount of preload used for the bearings. Great.

Got the carrier out and tried it out on the bench. Still not moving. Ended up taking the ring gear off and splitting the carrier open. The locking sleeve came right out. So that wasn't it. I then had to pull the bearing off the end so that I could take the seal housing off and see if it was a plugged airway after all. Surprisingly I got the bearing off without destroying it by using a bearing splitter, a big chunk of I-beam, a couple pieces of angle iron, and my 20-ton shop press. Came right off, easy peasy.

Took the seal housing off and looked at the opening. Sure enough, it was plugged with crud. Brilliant. Cleaned it out and a bunch of crud came out. Everything else looked ok so I attempted to put the seal housing back on. Of course I didn't notice the lip of the flange it goes onto was not chamfered so I buggered up one of the o-rings a bit. Which calling them o-rings in the parts diagram is a disservice. They are not o-rings. They are circular seals that actually have a X shaped profile. So not something you'll find at any parts store. Or even online in the USA for that matter. Only can get them from either overseas suppliers or ARB themselves. Nice.

Anyway, got the seal housing back on after chamfering the lip and then put air to it. The bonded seal that acts as a piston against the locking sleeve popped right out. Good. I guess.

Put the bonded sleeve back in after cleaning everything up and closed the carrier back up. Moment of truth. Applied air. Locker works! Except now it leaks air like crazy past the bonded seals. Good grief...

So now I have ARB sending me a new set of seals for the seal housing and the bonded seal. They were really good about it and did it under warranty.

Made a splice coupling for the copper line by taking a brass 3/16" tubing splice (the "Christmas tree" kind), cutting the ends off to leave just the middle part, and drilling it out with a 9/32" drill bit and then soldering it all back together with high strength lead free solder.

So now the locker is all cleaned up and just waiting on the seals to arrive and then I can get it put back together. I have been trying to talk to the guy that did the diff originally and he says he is willing to fix it for me, though I'm not sure if I want to go to the trouble of having to take the axle housing off the H3 and transporting it almost 2 hours south to his shop and then waiting on him to put it all back together for me. I'm concerned about the apparent lack of preload as well. I have never done a diff before which is why I took it to someone else in the first place, but after this I doubt I'll ever do that again. There are literally only two things I have never had to rebuild myself before on a vehicle. Transmissions and differentials. I've done pretty much everything else. Automatic transmissions are pretty touchy from what I have gathered (and for the price I got my rebuilt transmission with warranty it was worth it to just go that route) and diffs were a bit overwhelming to me with how easy it supposedly was to do it wrong and wreck the gears. After this though I think next time I'll just take care of it myself. If I can rebuild an engine no problem a diff shouldn't be too hard either.


Here is a closer look at the jam nut before I put it in some Evapo-rust to clean it up, but after I cleaned it with a wire brush:

And here is the splice in the copper line:

 

[JPaul]

Seals arrived Wednesday, ended up not getting around to installing them until today. No leaks now! But of course I forgot to put the side gear back in, and then when I took it back apart to get that in I realized I might have put the bonded seal in backwards. So now I am waiting on ARB to reply to my email about that question. But it's looking better now. Hopefully I'll have this back together soon.

I'll be going down to Ogden tomorrow to get the new tires mounted to my spare set of rims. Since I don't know for sure when I'll have the diff back together I want to go ahead and get that part taken care of so that they aren't sitting at the store for too long.