Chevrolet 6.6 burning oil

Greene728 wrote:
I’ve got a mint condition 2016 Silverado 2500 CC 4x4 and the 6.0 with 4:10’s that just turned 60k miles. I get asked often if I’d sell it. The answer is always no. Or at least no one has offered enough yet! Think I’ll hang on to her a while as posts like this are all to common on different forums.

As far as the 7.3 Ford gassers. We run a number of them in our ambulance fleet. 11 ambulances with a distributed call volume of 23,000 plus a year. Also have 4 F250 Battalion Chief trucks with them. One truck is at Ford now for engine replacement due to a lifter issue at 12k some odd miles, 2 ambulance have had engine replacements (one lifter, the other I believe valve issue going down into the engine) and numerous other issues like plug wires, coolant leaks, and oil consumption. Now admittedly, the ambulances get run hard. But all were low mileage issues, like well under 50k miles. I know the engine really hasn’t been out that long. But so far, they have been nothing like the pre 2020’s that had the 6.8. At least for us. Those engines took a beating and kept on rolling! YMMV.

The 6.6s have been out since 2020 - there are plenty of trucks now that are higher mileage. The consensus is that there were issues with brakes (loud like trains) and a few electronics issues like dead radios etc. Oil consumption has been talked about in all the groups every now and then but the consensus is that the majority of the trucks do not consume oil and the ones that do - do it within the GM guidelines/expectations (there is a 2020 bulletin about it). I think GM did the right thing to pair the new engine with the tested 6-sp tranny and that way work out all the bugs / limit the variables that could go wrong. Now GM is going to the 10-sp tranny and some people are ecstatic, some are not. Overall, the 6.6s have shown to be good and strong engines and IMHO the most reliable/least problems from all the 3 HD gas engines. Not the most powerful but most reliable.

p.s. this is from the GM TSB:
"Oil consumption of 0.946L/379L of fuel (1 qt./100 gal.) or less is considered acceptable."
https://static.nhtsa.gov/odi/tsbs/2022/MC-10211061-0001.pdf