GMT 800 Thoughts? aka 2006 Sierra

[online170]

There is a big question on buying a low mileage truck - at this stage none of the front end susp. components have been renewed. Wonder if it makes more sense to buy a higher mileage truck that already had wear items replaced?

Exactly!!!!!

This is why i said, i would have zero issues buying a 250,000kms truck, because it didnt do the 15minute runs, and actually warmed up and had all its fluids/greases circulated. Maintenance was likely kept up and its probably more reliable. Parked vehicles develop alot of repair issues, they werent designed to sit around forever.

Thats probably why we need to wrench on classics constantly haha.

 

[grandamman]

Although I have a 95 with 360,000 miles and running ridiculously well, I'd go with the 2006.

 

[olds307 and 403]

Also, take the trans dip stick, wipe off onto your fingers and give it a sniff test. If it smells burnt, walk away. Thats a really expensive repair.

Yes, and very common too. The 3/4 clutch packs fail often. As said the 5.3 has very little low end torque. The Vortec 350 is much better than the 95 mentioned above, power wise, mixed reviews on mileage. I had a 94, those swirl port sbc TBI 350's were a joke. The Olds 350 with 307 heads I put in it way out performed that turd. Mileage between the two is a toss up, the 5.3 should do better and the Vortec 350's did have some issues.

 

[joesregalproject]

I had two GMT400s, a 99 Suburban K1500 with the Vortec 5.7 and a 96 K1500 with the Vortec 5.7. I had a company truck that was a 2006 Chevy 1500 crew cab short bed with the 5.3, and it was better in every conceivable way that the GMT400s I had owned. Fit and finish, materials quality, power, comfort, ride, handling, fuel economy, etc. I tried to buy it when I left that company but they wouldn't sell it to me. I'd have no problem buying another GMT800.

As for pre purchase inspection, I always bring a creeper and get underneath. Poke around, see what the rust is like. Scale isn't a big deal. Holes are. Check for obvious cover-ups, as stated like the rubberized undercoating. Check all the things people forget- brake and fuel lines (are they rusty?), emergency brake cables (do they look like they are about to snap?), exhaust, especially around the joints and the cats. Bring a pry bar and check for play in the ball joints and tie rods. Check for play in the driveshaft u-joints. I always crack open the radiator petcock for a second to see if any crud comes out.

Once your up top, smell the ATF as suggested, check under the oil cap for milky sludge (condensation, usually means lots of short trips).

Check to see if the AC works, if it doesn't press the nipple on the low side port for a second and see if there is any refrigerant in the system. If not, you have a leak somewhere, if there is pressure, likely a problem with the AC clutch or electronics.

 

[ed1948]

Thank you for all the helpful replies.
I may look at an 04 Chev, 4.8, manual conveniences, chrome steel wheels, rubber floor mats, 120K miles. Problem is I'm not happy with the Chev grille and lights and prefer the Sierra look....but.....!!
I've been truck hunting for GMT400's since September - the sellers think I'm nuts for taking at least 1/2 hour to crawl under and snap pics. I have quite a large collection of the ugly underbody pics I've taken.
Beloww - either too high mileage or too high asking$

 

[pontiacgp]

we had a GMC 1500 with the 5.3 which we used to haul the race car all over Ontario every summer for about 7 years. The only problem with the truck was the rear disk brakes, the driveshaft twisted a little and the intake gasket after 350,000 kilometers.

 

[ed1948]

350K km is not bad..
I want rear drums which the 2005 has.
I believe there might be ways to 'tune' the 4.8 so it too can twist driveshafts😆

 

[rogue_ryder]

I looked at a 2006 Sierra SLE K1500, 90K miles, non smoker, orig paint, 5.3(driven in a salty winter area) prices just higher than average
The frame has surface rust(little scaling), fender lips and rockers (except one small area)are solid, rear brake lines and parking brake cables newer, bumper rebars are scaly but solid
Anything I should be aware of during the test drive?

The other truck I'm considering is a 96 K1500, 350 Vortec, repaint 10 years ago, no winters since, driveline original, 200K miles, looks new. This costs 2/3 of what the 2006 is going for.

It's tough to find a clean, solid truck around southern Ontario that does not require body work.

Go with the GMT800! Even if the particular one you're looking at doesn't work out.

I've got 175K on my 2006 and it's the best truck I've ever owned (picked it with 123K on it a few years ago).

Some common problem areas:
Transfer Case Encoder Motor and/or the Dash Swith (If you get an LS level trim it's a non-issue as they have a shift lever on the floor) the grounding wires are below the door and cleaning those grounds up can help with preventing the parts from going out. The good news is it's a cheap and easy fix to replace both the switch and encoder motor.

Cheap plastics (The tailgate latch and clam shell door handles break often)

PCV in the valve cover can cause oil to burn when it gets clogged up. If you don't fix it or clean it you'll ruin the cats. New Valve cover with the updated PCV is <$100.

The newer the truck the better the transmission. 4L60e<4l65e<4l70e each revision got beefier parts.

The 4.8/5.3 & 6.0 are miles better than the old Gen II Vortecs; they make better power, have better fuel economy and seem to last longer (not uncommon to see 300K on these motors).

I did a ton of research on 4wd 1/2 tons before buying mine. The "LS" can't be beat for reliability when you compare it to the competition. Although the interior is crappier than Ford or Toyota and probably equal to Dodge. The Ford and Toyota are a much better platform for putting on better off-road suspension systems (Torsion bar vs Coils). Chevy parts are probably the least expensive to buy as well even for the top tier replacement parts. Price out rotors and pads for a Chevy vs the competition.

Deboss Garage has a good video on youtube about these trucks

(he's up there in Canada so pretty relevant to your situation).

 

[ed1948]

Pictures do lie---I looked at a

120|K mile 2005 Silverado - obviously a repaint: wavy rockers(slip on), painted over lower fender rust, holes in front fender liners, rear fender liners patched with ?, frame crossmember at the point of being porous, poor attempt to blackcoat sections of the frame, primer inside the gas filler cap etc. Wonder if the average used truck buyer cares.

pic of inside rear fender lip and photogenic truck

Those body shop 'butchers'.(sorry to all the pro body people). The reason I could not feel holes in the rear wheel tubs to fender joint- they smeared some sort of epoxy layer in the gap left by the rust hole(grey material). By doing that they eliminated the drain holes.

 

[ed1948]

What do you think about Dodge 1/2T 4x4 from 2004 to 2007. My Son likes them (as a mechanic) and says he would buy one. I feel more comfortable with GM's having DIY'd on GM trucks from the 70's through 90's