How reliable is the 6.6 gasser?

HyperX · February 8

I have a 2019 Duramax Chevy and had no real issues with it. Since I am going on 5 year ownership with it, I would like something new. I got rid of my boat, so I do not need to tow but I always utilize the bed so I need a truck. I was looking at 1500 Chevys and GMCs and the engine issues with them are scaring me. So I figured I go to the 6.6 gasser and again back to the 2500. Question - is the engine reliable? I do not see too many topics where it goes bad. Is there anything else I need to worry about? I just need another truck that gives me 5 years of trouble free operations as I drive a lot between my two homes in IL and FL.

Thanks!

diyer2 · February 8

Keep what you have.

sigmonster · February 8

I think they are very reliable. I only nave 8000 miles, but no oil usage or issues. New trucks ride much better than 2019's and have better infotainment systems. Mileage will be worse, but regular is cheap and $ per mile is very close to diesel.

Pryme · February 8

Mine has been perfectly reliable for the 18mo I’ve had it so far. No oil usage at all. 8qts in 8qts out.

TeamSaris · February 8

25k on the tow rig. doesnt live a particularly easy life. zero oil usage, never misses a beat

the 5.3 in my 1500 has also been great other than 1 coil pack. im looking forward to trading it for a 6.6 gas hopefully soon. the AFM/DFM is not the best for a truck somebody plans on keeping forever...i like how the 6.6 is a simpler engine. NO clue why someone above would say "keep what you have"

diyer2 · February 8

Keep it because no issues, why replace it. Because money is burning a hole in your pocket.

TeamSaris · February 8

because he wants something new and he can. don't insinuate there's a problem with the 6.6. he didnt ask for financial wisdom

diyer2 · February 8

Didn't say there was a problem with the 6.6. I gave my 2 cents.

HyperX · February 8

I may keep the diesel, but the reason I want to go back to gas is because these -30 degree weather has really messed with me. Apparently I forgot I tanked up in a southern state, and it had no diesel winter fuel treatment and it was not fun trying to start it. Totally my fault, but something I dont want to deal with.

Another JR · February 8

My 2021 cclb SLT gas at 3 years and 11k miles has been trouble free, smooth, quiet, and powerful, and is a really comfortable and easy to drive highway vehicle. It’s huge though. I’ll point out that the gas hd truck subforum (this one) will often get up to 5 days with no posts. Very few appearances in the troubleshooting subforum as well.

Gas-specific issues I remember seeing on here over the last 4 years:

1) Some people complaining about high oil consumption, with others saying they have almost no oil consumption. Mine is the latter.
2) A few reports of leaking oil cooler tube assemblies

3) Debates over whether one ought to add a catch can to the crankcase ventilation system (I haven’t and won’t)

4) People worried about whether direct injection will lead to heavy intake carbon deposits (hence the catch can debates).

I would have no hesitation recommending the gas truck if it suits your needs.

Buy the configuration (trim and options) you really want though. There are a lot of posts here from people who thought they could buy a lower trim truck and add features that are on the higher trim trucks, but find that many of those features can’t be added at reasonable cost or can’t be added at all.

Make sure you sit in the seats before selecting which ones you want. There are big differences in shape, feel, and comfort that are subjective. I really like the seats in my SLT with leather bucket seats and console.

Texas Gasser · February 11

I have had my '24 LT for just over 10 months with just over 11000 miles and have had zero issues with it. No loss of oil and pulls my 8000 lb travel trailer just fine. Love the 10 speed transmission as it does a great job of keeping the truck in the power band and does a decent job of engine braking. It rides well for a 2500 HD. When not towing I keep the tire pressure at 60 psi to help with the ride quality. Love the truck so far.

UWSkier · February 12

My 6.6L gasser gets worked pretty hard towing in the mountains in the Southwest in the hot summers. I've had it less than a year, but so far, so good.