Calling 2020+ GM 25/3500 6.6 Gas Owners

This was my experience with two GMC vehicles, both with the 5.3L v8. I would consistently burn a couple quarts between 5k oil changes. All so half of my engine could shut down to earn me 0.1 more MPG while cruising.

The people who demand (and approve) these kinds of measures out of auto manufacturers are not serious people.

 

What do you need a truck for, then?

 

I don't "need" a truck.

I "want" a truck.

 

I've got two oil changes (11k miles on the clock today) and haven't experienced any oil consumption. Definitely something I'll keep an eye on.

 

I'll add:

every God fearin', grown ass man should have a truck in the stable.

a supercharged truck earns you bonus points.

 

If I didn't need the truck capability, I'd rather drive a SC Tundra than a SC 3500.

 

One of my coworkers has a 2021 Ram 2500 Cummins Limited Megacab with only 1700lb of payload. Says it's good for pulling his 8,000 pound camper at 85 mph.

 

did/does the 6.6L suffer the same lifter malady as the 6.2L?

or is it a complexly different design?

 

Is the oil consumption seen in these high stress motors being recycled into the intake via PCV and could be captured in a catch can? Or is this legit burned oil from ring blowby (I would not suspect this?)

 

I too would take a Supercharged 6.6 L8T over the diesel for my particular use case, even for the same cost. I’d rather have 600+hp and 700+ ft lbs than 445hp and 910 ft lbs. That’s also assuming a less than ideal out of the box cookie cutter tune from the blower manufacturer. This is easily a reliable 800+hp gas engine with a blower, smaller pulley and proper tuning. I know Harrop has them running over 1000hp with their TVS2650. All it would likely require is feeding it a lot of gas, which never bothered me! I’d rather that than DEF and costly out of warranty emissions equipment failures.

Huge torque is of course important for hauling, but slightly less huge torque combined with huge horsepower is even better IMO. If I was using the truck as a hotshot driver hauling campers across the country or pulling a skid loader on a daily basis, I’d have the diesel though most likely.

 

I don't believe so, mainly because they don't have the d.o.d. mess. . Atleast the people I know that have the 6.6. dont

 

The 6.6 doesn't have the AFM/DFM/DOD system that the 6.2 and 5.3. do. But, that being said, I'm not sure if that was the root cause of the issues or not.

ETA: I see this has been answered already.

 

FWIW.....I had a 2015 Silverado 1500 with the 5.3 that had AFM. This was where only 4 of the 8 cylinders would drop offline to appease the epa. And yes.....from having dealt with a collapsed lifter at 87K miles or so and doing a lot of research on the Silverado/Sierra forums, it appears that the engines with the AFM or even worse now the DFM where any of the 8 cylinders could drop offline......seem to be the ones with the lifter issues.

I was all set to keep that truck and have a shop do a complete AFM delete kit and throw long tube headers and a tune on it but I started having unresolved electric issues at 96k or so which forced my hand and helped get me into the Tundra.

I am glad I made the switch to the Tundra!

 

My understanding is the heads that were put on those motors had poor geometry with the push rod. They simply didn’t align right and gm went ahead and used them

 

I have the reroute to a catch can and have not seen oil consumption to a material level. I don’t measure after oil changes but I’m usually always putting back 8qts so I assume minimal oil burning.