2002 2500HD - Solid Axle Tow Rig

I did, in fact, wash the truck last weekend. Of course, we're getting the remnants of a hurricane now...but it was clean for a few days!

I loaded and then unloaded 2100 lbs of scrap metal yesterday. I'm sore and I'm not sure it was worth it for 175 bucks. It's out of my way though. The front end was pretty light going down the road!

Yes, that is an old school, cast iron, bathtub insert mostly full of cast iron. I also had all the old undercarriage parts from my old excavtor, the old coupler, and a bunch of car/truck parts I had replaced over the years. The rat bastards paid me steel price for all of it, even the clean aluminum, dirty aluminum, and magnesium.



Big time, major things going on over here....

ABS light has been on for a while. Needed to rotate the tires and grease the front end before going to Florida next week, so perfect time to do it. The sensors that were in it were out of the old IFS hubs, so no telling how old they were. The new NTK ones come out of the side of the sensor at a 90°, which is helpful.

As soon as I got over 10 mph the light went out. I was definitely tired of looking at it. Also discovered a bit of slack in the RH upper balljoint. Might have to look in to some of the fancy/expensive ones.

My first thought was DynaTrac, but I like the EMF ones a little better. They have have to be removed from the knuckle to be rebuilt. Any suggestions from you guys?




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EMF absolutely kicks ass.
Klayton is a BAMF anf his products are awesome. he gets my vote.

Can you expand on the ABS issue ? Mine has this problem where the abs light is on and data stream from pass side sensor drops out under 30mph. When I go back over it's good. New sensor.
What truck?

My issue was just old crappy sensors that quit reading. They were also different length sensors for some reason, so I had shims under them to get the air gap right. I stuck these in and spun the hub to make sure the magnet in the tip wasn't touching the tone ring. They didn't, so I just bolted them in and went with it.

01-07 classic HD trucks have a passive ABS system. The tone ring spinning past the sensor tip creates the signal and sends it to the BCM. Rear ABS works off of the VSS through the ECM. Newer trucks have an active ABS system and generally have 4 ABS sensors/traction control. The sensors don't create signal voltage. They get set power from the ABS module.
Bad wheel bearing?
Gave the old rig a bath. Washed, dried, a coat of glaze, and then wax. My shoulders are killing me from waxing off so much :D

Wish they'd make a truck that looked this good again.



It got a helluva workout today. Ran the pure tee hell out of it for 12½ hrs at 80-90 mph :D Have I ever mentioned how much I love having a 62 gallon fuel tank? Never stopped for fuel in 850 miles and still have enough to get back and forth to work all week!

@Bebop I'd throw a (high dollar) scanner on it and pull ABS codes. Has to be one that will access the BCM. Mine said both sensors shit the bed. Replaced them...fixed it. Hopefully it's got a code stored and can steer you in the right direction. Maybe the left one is acting up since the right one got all the attention? :D
@Bebop I'd throw a (high dollar) scanner on it and pull ABS codes. Has to be one that will access the BCM. Mine said both sensors shit the bed. Replaced them...fixed it. Hopefully it's got a code stored and can steer you in the right direction. Maybe the left one is acting up since the right one got all the attention? :D
Front right sensor code.
The data stream interrupts itself when under 30ishmph and picks back up after.

I put new bearings and sensors on it on both front wheels and even flipped them around to check. No change.
Not sure how...but maybe the air gap is off? For a passive setup it should be .017 to .039 max, if I remember right. Other than that...maybe a chaffed/corroded wire on the truck side? Possible BCM issue?
Not sure how...but maybe the air gap is off? For a passive setup it should be .017 to .039 max, if I remember right. Other than that...maybe a chaffed/corroded wire on the truck side? Possible BCM issue?
No idea how to measure the gap.

I need to check the harness for sure.

Does it go the the BCM ?
Yes. Front ABS is read through the BCM and the rear via the VSS through the ECM. Took me a minute to figure that out, but I did. Why GM decided to do it that way...I'm not sure.

I measure it with a pair of calipers. Measure from the bottom of the sensor tip to the underside of the shoulder. Then use the depth rod to measure from the sensor mount surface to the top of one of the teeth on the tone ring.
Everything is still going pretty good with this thing. It's about time for some regular service items as I have racked up some miles in the past few weeks. I think since I left for Florida until now, I've probably added 2500 miles or so.

Need to balance the tires. I just rotated them, but there's a small vibe since a few big burnouts. Go figure 😅

Definitely time for all three fuel filters.

Probably do a dump and fill on the transfer case.

Biggest thing is the initial 5000 mile service on the transmission. I'm actually at like 5600 miles, but oh well. I'll do that once the new pan shows up. Dump fluid, pull the pan, replace internal filter, reinstall the pan, change external filter, fill it back up with fluid.

The stock pan is fine, but I just wanted to spend some money on Black Friday and had a few extra bucks. I snagged a PPE shallow pan just for shits and giggles. If nothing else, it will look snazzy and has a better drain plug seal that won't tear and will let all of the fluid in the bottom of the pan drain out.

Eventually I'll snag some of them fancy balljoints from EMF and get those installed. I'll probably go ahead and put the TrueTrac in the front that I've had sitting here forever along with an install kit. The inner axle seals have leaked since I installed them and these big ass knuckle seals are pricey/a pain, so I'll do it all at once.

Oh, I did finally snag another set of center caps and cut two more out for the front. I crushed one a while back. Whoops 🤷‍♂️

I haven't managed to get much done lately while adjusting to a medication change, but I did come home from work tonight/this morning and get this CTS2 mount put in. Managed to sink a razor blade in my thumb too, but oh well.

I think I like it. Especially for 20 bucks. There really aren't many good places in the 01-07 Duramax trucks to mount a monitor and this much better than a shitty suction cup on the windshield. I don't think anybody uses that little cubby hole anyway.








In other news, UPS lost my transmission pan. I opened an investigation and they miraculously found it in Ohio the next day...go figure. It should be here on 6 Dec, so I can FINALLY service the transmission.
I got 4 different emails and each had a different, updated delivery date. UPS is killing the game! It's actually out for delivery today, so I'll be late to work this afternoon since it requires a signature and I don't intend to play this game with them any longer.

Hoping to swap it out tomorrow morning.
FINALLY! Looks like I have something to do tomorrow before work :D

I have to say, it's a very nice product and VERY well packaged. It had corner protectors over it and everything. Kuddos to PPE, as always. The drain plug is almost flush on the inside and should let pretty much everything drain out in the future. Plus, it looks pretty damn cool and will match my lower oil pan. 😎




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Finally got the service done this morning. I forgot the new Allison filters are black, which is cool, and everything is esthetically pleasing if you happen to be crawling around under my truck.

Not too much schmootz on the magnets, but an expected amount for a break in period. It definitely shifts smoother now. The filters that were on it weren't actual Allison branded filters. So, between that and them likely having plenty of stuff caught up in them, it makes sense. I was gracious with the brake cleaner, but unless you've got a wash cabinet it's pretty hard to get the transmission case REALLY cleaned out.

I dumped in a fresh gallon of fluid I had left over from the build and then poured the fluid I had drained out back in to the gallon jug. Of course, I filtered it through a tightly woven, lint-free rag. Good as new :D I had a hard time thinking about throwing out transmission fluid with 5800 miles on it.

Anyway, here's some pics.




Finally doing a bunch of little stuff that I've been putting off.

Replaced the backlights in the heat/AC controls a few days ago. You never realize how nice it is to be able to see those things in the dark...until you can't. I kinda burned up one of the solder joints. Oh well, it's not worth the cost of replacing the whole panel for that one button light.





Got around to changing the fuel filter and water separator on the lift pump today. I was going to do the underhood one too, but it's not quite due annnd I may have run out of daylight/said "F it" for now :D However, I always need to pump the primer to help suck fuel back in to the lift pump after a filter change and I discovered that needs a seal kit again. A lot of folks say to ditch the stock filter head, but I prefer to keep it for instances like I just mentioned. Plus, I have an adapter on it and run a BIG, spin on fuel filter instead of a stock one.

I had also been having a nagging fuel drip at the bung in the sump of the fuel tank. JB Weld Plastic Bond appears to have gotten me hooked up. I brake cleaned everything, scuffed it up, cleaned again, and smeared it all around. So far so good. Hopefully it stays that way.



Next up is body work...again. I'll likely be replacing the front bumper with something aftermarket as evidenced by my other post. We'll see how that goes.

I also have a Detroit TrueTrac and master rebuild kit for the front axle. I need to snag that same setup for the rear as well. I'm also really considering going to 4.10s. It'll be a lot happier while towing if it's turning 2000 rpm at 65 instead of 1800 rpm. 2300-ish at 80mph will be fine. I'm not scared of letting it eat!
So far, so good on fixing the fuel leak. I like that Plastic Bond stuff. Well done, JB Weld!
Truthfully, there's never any telling what I might wind up doing on the weekends or what kind of somewhat, mildly sketchy shit people will ask me to haul or move for them. Sorta like this...

They just asked if I could move "a shed". Sure!

🤔 🤷‍♂️

I made it happen and it was disappointingly not a sketchy process. Oh well.