What did you do to your GMT today? [Part II]

[Mooseman]

Took the TB in for a new set of shoes. Got the same Nokian nAT All Terrains that I got for the Sierra. Loved them so much on the Sierra that I decided to splurge on the old girl. The winter tires I had on there were worn and old and driving in snow has not been fun. And since the summers were also over 10 years old, decided to get an all-weather tire I can use all year.

Unfortunately, I let them talk me into "checking the alignment". Of course they said it was off. I had it done last summer at the dealership before I quit there and it was the best alignment I had ever had and was still good. Now it does track straight but the wheel is off-center . Gonna go back to get it done again but they'll get a face full of snow when they put it on the rack since it will be a storm tomorrow. I knew I shouldn't have done it.



Anybody want a set of Envoy chrome rims with old winters?

 

[Mike534x]

Got some progress pics for you all that he sent over! Bright side is, I caught it in time! The downside is, there's a small bit that's rusted/rotting out thats hidden by the cross member/CAT. He was working on her last night, and found it while beginning to clean the inside of the frame. Figured you guys would appreciate seeing what it looks like from the inside out.

Should be ready this weekend, to help me out he's painting the inside frame rail, and the outside by the cat with multiple coats of that chassis saver. It should keep it from getting any worse until I bring it back over the summer for him to work on it. According to him it's better then POR15, and from what I've seen it has good marks online from the Tacoma community.

 

[Mooseman]

It's crazy the amount of frame rust you guys down south get whereas I haven't seen anything like that with three GMT360's. Only other truck I've seen and fixed was my son's 2011 Silvy but he's up north and they use brine on the roads there, which is what I think is also the problem in the US rust belt. We don't use it in my area, just regular road salt, but I always get my vehicles oil sprayed. So far, my 07 TB has just a few rust spots on the front hood lip, one corner of a rear door, bubbling on the rear roof corner at the seam and the rear hatch lip.

 

[Mike534x]

It's crazy the amount of frame rust you guys down south get whereas I haven't seen anything like that with three GMT360's. Only other truck I've seen and fixed was my son's 2011 Silvy but he's up north and they use brine on the roads there, which is what I think is also the problem in the US rust belt. We don't use it in my area, just regular road salt, but I always get my vehicles oil sprayed. So far, my 07 TB has just a few rust spots on the front hood lip, one corner of a rear door, bubbling on the rear roof corner at the seam and the rear hatch lip.

Tell me about it Moose. I'm in NWI (20 min East of Chicago), and they go nuts with the salt over here. Its bad, but nowhere near as bad as the East Coast, like in Eric O's area where its just completely gone after a few years. Some of the Midwest uses brine, but we're still using salt unfortunately. We did have one year where there was a salt shortage, and we used sand which made it the easiest winter to deal with. I wish they'd use that instead.

Anything GM here rusts out badly, especially if its a GMT800. I have yet to see one that didn't have nearly every body panel rotted out. My Dad's 06 Yukon has the rockers rotted out, but the frame is still good from the undercoating I did 3 years ago. It definitely needs a touch up, used cosmoline, and it went on nice but its flaking off badly. The Trailblazer has spot inside the rear door near one of the drain holes, it hasn't bubbled/eaten its way to the outside metal yet. The Envoy has a section by the rear fender by the gas door that's been bubbling for awhile, but its not fully through yet.

 

[Mooseman]

So my saga with the alignment is finally over. Third time's a charm. Took it in again yesterday and they redid it. Driving it home, the wheel was still off center tilted to the right. Took it back in again today and finally it's straight ahead. I think he just readjusted the front wheels so to turn the wheel to the left. Never again will I get a "free" alignment check.

Anyway here are some pics of the new tires. They do look good and traction in snow is phenomenal.







Thinking this summer I'll repaint the wheels.

And... I'm now getting ABS and Stabilitrak lights. Codes C0035 (LF wheel sensor), C0455 (Steering wheel angle sensor (known intermittent issue)), C0244 (PWM Delivered Torque Malfunction). I probably have a wheel bearing starting to fail and I have to update the ABS module as per @mrrsm 's TSB he posted for the SWPS error.

 

[Mooseman]

Replaced the turn signal module. It had been flaky lately where it usually didn't want to work the left turn signal unless I flicked it twice. Very annoying. I had the old one from the 02 I kept as a spare so $0 fix. Also had the one from the Saab but it is vastly different because of the HID and the turn signals as a DRL. I should put all these Saab parts on eBay.

 

[TollKeeper]

Drove it for just short of 1000 miles in the last year, and it needed emissions. Passed with flying colors.

While sitting in line, there was a 2006 Volvo XC90 V8, which is a vehicle I was considering.. Glad I didnt I think. It maybe that she was having it serviced only at the dealer, but every repair bill has been 3000 to 10000. She has put $19000 in the truck since last January 2024. More than the truck is worth! The V8 is cool to drive, fast, and peppy. But at those repair prices, I think I will pass!

 

[Mike534x]

Forgot to post the repair pics, this was after I picked her up Saturday evening. The chassis saver was still a bit wet, but otherwise it looks good! Coating has cured, and after banging around it feels very solid like the factory metal. Overall, for the price, I'd say it was worth it keeping this thing going especially with what I spent so far, and what I've spent on fixing her up. She's stored in the garage right now, waiting on a can of Eastwood Rust Encapsulator to show up to touch up a few spots elsewhere on the frame. At least until its nice enough out to climb under and not freeze while coating it fully with Woolwax.

Driving the Envoy for now, since the frame is still well protected and to get some of the old gas from October used up. Still watching the battery levels as she sits for a day, since the phantom draw is only during the winter I'm leaning towards it being a module thats the issue since it can sit for days when its warm out and be completely fine. So far I'm averaging 14-16 with city driving.....beating out the Trailblazers 12. Not sure if the Envoy's 3.73 gearing over the 3.42 makes a difference or not.

 

[TollKeeper]

Drove it for just short of 1000 miles in the last year, and it needed emissions. Passed with flying colors.

While sitting in line, there was a 2006 Volvo XC90 V8, which is a vehicle I was considering.. Glad I didnt I think. It maybe that she was having it serviced only at the dealer, but every repair bill has been 3000 to 10000. She has put $19000 in the truck since last January 2024. More than the truck is worth! The V8 is cool to drive, fast, and peppy. But at those repair prices, I think I will pass!

Quoting myself here...

Drove 6068 miles in the last 2 years!
Emissions done in 2023 at miles 212104
Emissions done in 2025 at miles 218172

Did an oil change on 5/5/2024 at miles 217677, or 495 miles since it has been done.

I really should get rid of the old girl.. But I cant. I really love my GMC, and its relatively cheap to own a spare car. only $30 am month in insurance, and about $90 a year in registration. SO about $450 a year. I think its cheap insurance.

 

[azswiss]

Rotated the tires. 55K miles on the Michelin LTX AT2's and there is still plenty of tread left.

 

[Mooseman]

So for a while now, the TB's HVAC was only sending air to the defrost, not the feet. Broke out the old Tech 2 and it had some codes.

B3761: Air flow control 3 feedback circuit
B0248: Air flow control 3 circuit

Cleared the codes and checked the door positions. All but the defrost worked perfectly. It would not go all the way to the commanded position when selector is to full defrost. Only went to 101 when commanded to 111.

Did a relearn of all the actuator motors, same thing but I might have screwed it up. Did it two more times and it finally took. Now getting heat on my feet and defrost is off when commanded.

While I was at it, the ABS light was on again. Scan gave me:
U1000: Comms error
C0244: PWM Delivered torque Malfunction
C0455: SWPS
C0035: RF wheel sensor

Cleared the codes and did a yaw rate recalibration. Maybe that will get rid of the SWPS problems. RF sensor could be the hub or the sensor getting rust jacked. The U1000 is a little more disconcerting. I'll see if this returns.

 

[littleblazer]

Brake job. (Just popping in as I do from time to time.)

 

[azswiss]

Tracked down a coolant leak to the heater hose tee at the firewall. Replaced this about 8 years back with a non-OE part (by comparison, the original OE part lasted 13 years). New OE parts on order (decided to replace both tee's while I am there). Video link below:

Heater hose connector leak

 

[Mike534x]

Tracked down a coolant leak to the heater hose tee at the firewall. Replaced this about 8 years back with a non-OE part (by comparison, the original OE part lasted 13 years). New OE parts on order (decided to replace both tee's while I am there). Video link below:

Heater hose connector leak

I had that happen on my Envoy back in 2019, there's a identical piece that sits further up on the V8 (past the dipstick) and mine completely broke in half where the quick connect seats into. Just not a fan of plastic being used on something like the coolant system.


Got the Trailblazer back the other day, the eBay special power steering lines the PO installed decided to crap out, well...the high pressure line did at least. Ordered new ones off RA, and had a shop do the work and all seems well. Only other problem I'm having is I think the TCC valve bore is worn, she doesn't seem to be entering lock up most of the time. Loaded HP Tuners, and went to the TCC max/min table, and set it to 100% for max, and 90% for min. From what I gathered, this should have the lock up function as an on/off. I don't feel the "5th gear" feeling like the Envoy's does with the delete, but I noticed the RPMs are lower during cruising speeds.

The TB has 3.42 gears, before the TCC edit she liked to stay at about 1700-1800 RPM while on level ground at 45-50 MPH, with the tune shes getting down to 1400-1550. Other clue was that when using cruise control going 55, the tach jumps up 200-300 every few seconds. So this is leading me to believe its a lock up issue either with the TCC PWM solenoid, or a worn out valve body bore.

 

[azswiss]

Replaced the two heater hose tee connectors at the firewall. Broke the retainer clip inside the connector on the inlet hose; fortunately it was available at Napa (Dorman makes them as well, available at AZ).