99-06 vs 07-13?

[Vamoosa]

So I did have an 05 Yukon my wife left me and she has that now.The 05 is at 200k and still runs perfect.My 02 Silverado is almost at 300k and runs perfect biggest problem with that in the last ten years was the little oring going into the oil pump went out a while back.I need another vehicle to use as family car when I have my kids.I would love to have a 99-06 but they almost seem to have a cult following in this area that comes along with ridiculous prices.The 07-12 are little more affordable.Have any of you owned an 07-12 and can I get the reliability of 99-06 in that generation?

 

[OR VietVet]

I have history with the 2000 to 2006 and none with the 2007 to 2013, except to work on them. I know enough to say, stay away from AFM engines.

 

[Marky Dissod]

Very general GMT900 advice - not cheap, but a 40oz of prevention is worth kegs of cure:
1. Disable V4 mode STAT.
2. Change oil more a bit often than you think you should, NOT LESS
3. There's a screen that needs replacing that's specific to V4 mode engines. Replace it ASAP (see #1).
4. If you can afford it, replace V4 mode hardware with V8 hardware - you already disabled V4 mode the week after you bought it, right?

5. If it has a 6L80E, replace the torque converter by upgrading it before it takes the 6L80E with it.

I'd bet that other GMT900 owners have more advice from experience. Ignore at your cost.

 

[Vamoosa]

Very general GMT900 advice - not cheap, but a 40oz of prevention is worth kegs of cure:
1. Disable V4 mode STAT.
2. Change oil more a bit often than you think you should, NOT LESS
3. There's a screen that needs replacing that's specific to V4 mode engines. Replace it ASAP (see #1).
4. If you can afford it, replace V4 mode hardware with V8 hardware - you already disabled V4 mode the week after you bought it, right?

5. If it has a 6L80E, replace the torque converter by upgrading it before it takes the 6L80E with it.

I'd bet that other GMT900 owners have more advice from experience. Ignore at your cost.

What screen are you talking about?I haven't purchased a vehicle yet but I have been thinking about it.

 

[Trey Hardy]

What screen are you talking about?I haven't purchased a vehicle yet but I have been thinking about it.

My 07 Tahoe is over 350,000 miles now with the afm tuned out and disabled but not mechanically disabled. Factory powertrain
You can most definitely get the same expectancy out of these models but they do have their quirks as they all do!
Main things I replaced was the front end,radiator and heater core Ts,battery alt and wiring,throttle body and ac compressor along with some ac door actuators and rear ac controls. I plan to drive her in the ground and when she does quit I’ll throw another motor in her and see if I can hit 700,000

 

[strutaeng]

I've got 3 GMT800s and really like them. Very low cost of ownership, but I've been doing all mechanic work myself in the last few years. No experience with GMT900s.

Seems like if you can do a DOD/AFM delete ($1500-ish maybe?) and keep the 6 speeds alive ($4500-$5000 rebuild cost), you should be able to make the GMT 900 pretty reliable. Some drivetrain parts like axles (and some axles were upgraded depending on engine option) carried over. Stronger 6.2 showed up in this generation, so that's "mo better."

 

[blackelky]

I think gmt800s are built better but damn near impossible to find in good condition with no rust. I like my gmt900 because of the modern conveniences and they way it looks. I have one of the later years so hopefully the kinks have been ironed out

 

[OR VietVet]

Lots of GMT800 rigs in the PNW and south with no rust.

 

[Alex_M]

I've owned both. I prefer the gmt800s for several reasons. Many of them are personal preference - the look, the feel of the seats, etc. Some of them are mechanical. AFM/DOD is a big one. Big ticket item to mechanically remove, which I did on the '07 Silverado I had (dad bought when new, kept until 180k miles). The electrical systems are a bit simpler on the 800s, especially the 99-02s. The sheet metal on the 800s seems a bit better, of course they're all older so more time for rust to take hold. Other than that, they're mechanically very similar. If I got a good deal on a gmt900 I'd be open to it, but they aren't my preference. No direct experience with the 6 speeds other than two of my mom's Tahoe's in a row losing transmissions due to torque converter failure. She's in a '23 Z71 Tahoe with lifetime powertrain now, so we'll see.

As already stated, every vehicle has quirks. I think the gmt800s are slightly better built than the gmt900s, but both are good vehicles.