2004 Trailblazer 4.2 - Newest Member of the Family

[dogememe]

Just picked up this Trailblazer for a good price. Initially when I learned of its availability I thought it was an 07 but it's actually an 04. No big deal... they're pretty much the same.

Second vehicle on this platform I've had. Had an 02 Envoy years ago... great vehicle.

Anyway, plans are to fix some odds and ends and take it to the snow when that time comes. Going to do a full service on it with all the fluids, because, well, this is BITOG, we do that around here when we buy a used car, right?

Overall it runs and drives great. These 4.2s are just such smooth engines it always amazes me. And for their size and especially for being like 20 years old, the GMT360s handle so well.

Plans are:
-Diagnose minor noise from front suspension, hopefully just a sway bar link.
-Alignment
-Tires (already ordered a set of Vredestein Pinza ATs and have an appointment for installation for next week)
-All fluids
-HVAC control issue, basically heat is cold and cold is heat on the temperature selection.
-Gauge cluster has some dead gauges. Common on these, my Envoy had the same problem.
-I haven't tried driving it at night yet but apparently one of the headlights doesn't work even with a new bulb.
-Thorough cleaning inside and out, with a quick polish of the headlights and some trim restore stuff, this thing will look NICE!

That's pretty much it for now! Anyone else on here enjoying their GMT360 still? The Bolt will still be my daily driver and will get 90% of the miles on it, because gas is expensive around here, and I get free fuel for Bolt from work sometimes, but it'll be nice to have something to go to the snow or camping or whatever, or if I have to go more than 250 miles at once lol.

BTW there's a really sad documentary out there, "the last truck: closing of a gm plant" which is definitely worth a watch IMO.

 

[D60]

I ordered a replacement cluster for an '02 and we opted for the blue LEDs. It actually was VERY nice I thought.

The owner didn't want to pay for programming mileage so it was 100k, but it really had something like 175 at the time.

Check the plug tubes for oil. Or wait for the misfire codes

It started to throw the notorious ABS code ‐‐ C0265 maybe?? I cleaned the ground down near the body mount but that didn't help. Usually an ABS module rebuild is the next step but we never got that far.

The wipers did the weird jerky thing. Opening up the motor and cleaning the grease out fixed that up perfectly.

The driver's seat always slid fore/aft like 3/8". He never asked me to look into that but I always wondered what caused it.

 

[dogememe]

I ordered a replacement cluster for an '02 and we opted for the blue LEDs. It actually was VERY nice I thought.

The owner didn't want to pay for programming mileage so it was 100k, but it really had something like 175 at the time.

Check the plug tubes for oil. Or wait for the misfire codes

It started to throw the notorious ABS code ‐‐ C0265 maybe?? I cleaned the ground down near the body mount but that didn't help. Usually an ABS module rebuild is the next step but we never got that far.

The wipers did the weird jerky thing. Opening up the motor and cleaning the grease out fixed that up perfectly.

The driver's seat always slid fore/aft like 3/8". He never asked me to look into that but I always wondered what caused it.

Yeah, on the Envoy I had before, I ordered a used cluster off eBay. It had lower mileage, but I used one of those labelmakers and I labeled the differential in miles in the door jamb so anyone could get the real miles easily, and made it very clear when I sold it. This time around, I want to do things nicely, as it has half the miles on the Envoy did and is in way better shape overall. I'll just order a reman one that's pre-programmed, I can just not drive the vehicle while I await the delivery, so mileage is exact.

 

[dishdude]

Looks nice. Everyone I know who had one of these was happy with them.

 

[super20dan]

everyone i know who bought one of these had nothing but endless problems

 

[dishdude]

everyone i know who bought one of these had nothing but endless problems

Of the 4 people I can think of that owned these all I can remember is a fan clutch being replaced.

 

[c502cid]

Of the 4 people I can think of that owned these all I can remember is a fan clutch being replaced.

Make that 5 people. Otherwise trouble free. It is an electronic (read expensive) fan clutch though!

 

[clinebarger]

I've had a couple in the family, 2003 Trailblazer EXT 2wd 5.3L & a 2005 GMC Envoy Denali 4wd 5.3L....Extremely high maintenance compared to a Tahoe/Yukon of the same year.

 

[dogememe]

I've had a couple in the family, 2003 Trailblazer EXT 2wd 5.3L & a 2005 GMC Envoy Denali 4wd 5.3L....Extremely high maintenance compared to a Tahoe/Yukon of the same year.

What type of issues did you have with those?

 

[Falcon_LS]

Yup, still got my Envoy. Congrats on the purchase!

 

[D60]

Even though it was '21, the same place is still around. They were easy to work with. I did first pull the original cluster and verify part #'s just to be absolutely certain (plus it wasn't my vehicle and I didn't want to look incompetent ordering the wrong part and creating excessive delays)

02 03 04 Trailblazer Speedometer Instrument Gauge Cluster w/DIC LED's | eBay

Fits 2002-04 Chevy Trailblazer. Rebuilt gauge cluster assembly with high quality blue LED illumination. Unit has been rebuilt with upgraded x27.168 stepper motors and high quality blue LED back lighting.

www.ebay.com

 

[14Accent]

Nothing wrong with a GMT360. Tough, tough trucks. Frame rot at the rear control arm mounts killed 90% of them up here, though.

I never cared for them, personally. They don't drive very well, they're woefully under powered with the 4200, and the interior's are bad even by GM standards of the time. Reliability wise, they're pretty tough to beat though. The do seem to munch A/C compressors, water pumps, P/S pumps, heck I guess just about everything on the accessory drive. Fan clutches are pretty steep, but they're not as expensive as they once were.

Packaging under the hood always bugged me on those, too. How GM managed to make an inline-6 so inaccessible is beyond me.

 

[michaelluscher]

Thermostats a PITA, OE GM part only
Same for the coolant temp sensor, or you'll scratch yourself bald wondering why it won't run a drive cycle

jeffescortlx does quality cluster rebuilds I hear, at a fair price

Those rear upper control arms can rot out, inspect them closely

I believe there was a recall for the drivers window switch pack overheating and starting a fire?
Run the VIN with GM, make sure it's had any (airbag?) recalls done

Consider an HVAC recalibrate/reset before you buy an actuator


Enjoy the ride

 

[D60]

{snip}
Packaging under the hood always bugged me on those, too. How GM managed to make an inline-6 so inaccessible is beyond me.

I felt this way, too. I thought valve cover gasket replacement was way harder than it needed to be.

And there's a 15mm fastener on the....p/s pump?.....that precipitated my purchase of 15mm in 1/4" drive.

I loved my '05 Canyon with I5/5sp, but never saw the appeal of the Trailblazers. Can't even call it a cute ute 'cause it's so ugly. Ugly ute I guess.....

 

[BrianF]

One thing I had done twice now was removing the front axle disconnect and greasing it.

I'm at 280,000km or so on my 2006. Around 169 I did shocks and struts and thought there was a bit of slop in it. It can be a pain the first go around but bearings are easy to press in and out and it's a sealed/greased unit.

Other than my ac dying and the abs/brake light on (cleaned the same chassis ground) it's a great vehicle and once I fix that stuff, my kids will begin to use it.

 

[JTK]

You still see some decent looking ones cruising around where I live, which is odd for any GM truck of this vintage. A co-worker of mine has a gold well used and beat Envoy that looks really nice yet.

As @14Accent said, check that rear frame area if you haven't and goop it up inside and out with fluid film or woolwax if that area is still salvageable.

I had a 2005 Trailblazer for few years. A white LS 4x4 that I bought as an ex-rental in 2005 with miles in the teens for $16K. Those were the days.

 

[Nick1994]

My grandparents had an '02 Trailblazer LTZ. Loved that thing. We sold it to the housekeeper in 2018 and they still have it. Same color as yours.

It wasn't perfect mechanically but it was ok. Needed a blend door motor so we just had my mechanic unplug it so it stayed on 100% cold. Fan clutch went bad, have to get the OEM one. We did the thermostat too but the aftermarket Stant one has a lot smaller opening than an OEM one, so we replaced that 2x. Motor mounts went bad, put in aftermarket ones and they lasted 6 months. Need to use OEM mounts. Driver's power seat motor went bad. Couple ignition coils.

Other than that it was just regular maintenance stuff, brakes, shocks and struts, etc.

One poster above said they're underpowered which I didn't find to be true, but ours had 3.73 gears. That Bose stereo sounded awesome.

I think this is the only pic I have of it.

 

[dogememe]

My grandparents had an '02 Trailblazer LTZ. Loved that thing. We sold it to the housekeeper in 2018 and they still have it. Same color as yours.

It wasn't perfect mechanically but it was ok. Needed a blend door motor so we just had my mechanic unplug it so it stayed on 100% cold. Fan clutch went bad, have to get the OEM one. We did the thermostat too but the aftermarket Stant one has a lot smaller opening than an OEM one, so we replaced that 2x. Motor mounts went bad, put in aftermarket ones and they lasted 6 months. Need to use OEM mounts. Driver's power seat motor went bad. Couple ignition coils.

Other than that it was just regular maintenance stuff, brakes, shocks and struts, etc.

One poster above said they're underpowered which I didn't find to be true, but ours had 3.73 gears. That Bose stereo sounded awesome.

I think this is the only pic I have of it. View attachment 234315

Nice! The wheels on that LTZ look much better, but I'm OK with the ones I got as the roads here suck and I'll take as much sidewall as I can get.

I don't find the 4.2 underpowered either. Plenty of get up and go. And impressive MPG for what it is.

 

[14Accent]

Nice! The wheels on that LTZ look much better, but I'm OK with the ones I got as the roads here suck and I'll take as much sidewall as I can get.

I don't find the 4.2 underpowered either. Plenty of get up and go. And impressive MPG for what it is.

I debated my use of the word "underpowered", I guess it's not so much the fault of the engine as it is the horrible gear ratios in the 4L60. The 4200 likes to rev, it makes peak torque at 3500 RPM and peak HP at 6k. All 275 of each.

Meanwhile, the 5.3 in the same chassis produces that same 275 lb. ft. of torque at a much more reasonable 2250 RPM and continues to pull up to 4k RPM. A much more realistic range for the vehicle.

Now, a 4200 in front of a 6L80? That could change the whole dynamic of the truck.

 

[BrianF]

I always believed the 4.2 would be great with 3.73 and a 6 speed auto. Would cover for its weak low end.