I’m in the market for a new truck come May. Anyone have any experience with new Chevy 6.6 gas engine?

I have seen out of a fleet of 35 GM trucks 6 of the 10 2021 6.6 gas engines eat cams already under the camshaft TSB and a couple were out of warranty. One even strangely dropped a lifter and yes they were maintained. Far as the 5.3 or 6.2 wouldnt touch one with 20' pole. Just got done doing another whole engine replacement from a failed AFM lifter and it wiped the engine out and took out the cylinder.

There hit or miss....you get a good one or a bad one.

Thanks for the response! I’m so torn on what I want. I tow 2 a fx 20 2 hours a weekend. I plan on keeping the truck forever. I’m just wondering if a half ton trans and rear end will hold up over time…. I like the eco boost and 3.0 duramax. But I can get the Chevy 2500 6.6 for cheaper or around the same price. I’m not super worried about the mpg but the other 2 are way better than the 6.6.

Yes I’m definitely staying away from the afm

If you’re not dead set on a GM, you might look at the Ford with the 6.2 or maybe even the 7.3 gas engine. The 6.2 is pretty much bulletproof if you are planning on keeping your truck for a long time

= 6.6 Duramax L5P

I know you are asking specifically of gassers but I had to add my opinion. I pull the same boat and have nothing bad to say about it.

You can find some that don't have the AFM due to the chip shortage. I just picked up a new GMC half ton with the 5.3 and I jumped at it for a couple reasons. one was it did not have the AFM activated due to the missing chips. And I won't be bringing it in if I do get a notice later.

I've got this too. Most reliable powertrain on the market is the L5P and 6-speed Allison

I don't know anything about that boat, but half tons should be able to tow most any boat, and will ride much better when unloaded.

The Ram hemi is a good motor, and their 8-speed transmission is fantastic. Ride quality is great, seats are really comfortable, and it's usually more affordable than other brands as well.

I am not set on gm. I have looked into the fords 6.2 and 7.3 and like them both.

Just tossing out another piece of info. My boss has a 22 GMC half ton with the diesel and the 10 speed, absolutely outstanding fuel mileage, and more than enough torque to tow just about anything you'd ever want to try and stop with a half ton. He's had it since October of 21, and loves it. His previous ride was a 17 F250 with the 6.2 gasser.

I can't believe some of the mileage figures being shown on video channels on the 6.6 2500's. People are claiming almost double what the old 6.0 4L80 trucks were capable of.

Yes I’ve done the research on that truck. I’m not in the market for any diesels until they get all the def issues worked out. I’m retiring in 4 years and want my truck paid off before I do. I plan on keeping the truck for 15 or 20 years. I just think diesel repairs and maintenance are going to cost too much.

That 6.0 was built for torque and reliability and the mpg was absolutely terrible.

There just aren't any really good reasons to buy an HD gasser. Go look at resale on diesel versus gas HD trucks and the up-front cost hit will seem miniscule.

I owned a half ton Ram ecodiesel for 3 years and put 67k miles on it and never had it in the shop except for one radio button that was replaced under warranty.

I've had this Silverado 2500 Duramax for a year and a half now and put 20k miles on it with zero issues.

Modern diesels don't have the same DPF/DEF unreliability of the 2007-2012 models when the rules were first implemented and it took them 5-10 years to work through the reliability problems.

I wouldn't own a 3/4 or 1 ton gasser myself, but the mileage people are claiming with the 6.6 is still pretty unbelieveable.

I ended up pulling the trigger on a 2022 Chevy 1/2 ton with the 3.0 duramax. A 3/4 is tough to come by right now… I’ll drive it and see how I like it. Maybe after all the supply issues are over, I can trade up if I want. I’ll keep everyone posted on how the truck does!

Gas truck may not have the resale but it don’t cost as much. Also if you keep a truck along time who cares.

I bought a new 2020HD with the 6.6 and when new was getting 16mg. Since then I’ve went to larger wheels and tires and it has dropped to 13.5. Runs excellent and could tow just about anything

Gassers have excellent resale.

This is not an exaggeration in any way....I have a 2021 AT4 with the 6.2 --- at 14,000 miles (last week) while traveling through Colorado both lifter banks went out stranding me in Woodland Park...after limping it to the Chevy Dealer in Colorado Springs and then spending 2000.00 on a rental to finish the vacation I picked the truck up on Saturday 7.23.22 - got on I-25 to head home and exactly 45 miles down the road the same thing happened AGAIN! I asked the Service adviser in Colorado Springs...How often do you see this? His answer..."A Bunch" most of the time they come back again for a second repair! I made it home fighting the truck all the way.

I will get this thing fixed and the truck will be history for me...no longer trusted. 2021 AT4 - my pride and joy is a total POS.

I've got a 2019 L5P and get around 20 mpg. Seen as high as 25 on pure highway and as low as 15 in pure city. Get 9-11 mpg towing my 9k lbs TT

What's a L5P ?
Duramax