Chevrolet 6.6 burning oil

[jabres]

Been a diehard Chevrolet gas, engine truck person my entire life. Use them very hard in my landscaping business, and the 6.0 gasoline never missed a beat. unfortunately the 6.0 gasoline is nonexistent, and I had to buy the 6.6 but I’m not happy about it. It has been burning oil since day one. Roughly every 5000 miles, it’s using 2 1/2 quarts of oil. it might even be more than that, going through an oil usage test with the dealer now. Anyone else have similar oil burning problem with their 6.6 Chevrolet gasoline? If it was an older truck, I would understand, but I just spent 50,000 and need to carry quarts of oil in my truck.
Thanks!

[larry_barnhart]

frankwp wrote:
If an 8.1 isn't burning oil, then it isn't running 🙂 Mine takes a liter every 3000 or 4000 Km

the 2001 8.1 engine we had used a 1/2 qt to 1500 miles when towing a 15K fifthwheel. Not an issue for me. chevman

[FishOnOne]

If you decide to purchase a new truck I would give the Ford 7.3 a hard look. Reason why is Ford stuck with port injection instead of direct injection like on the Chevy 6.6 engine.

Good luck...

[Grit_dog]

CWilson wrote:

Grit dog wrote:
Whoa, sorry for being a month behind on GMs next years models….lol.
Well good, GM finally pulled their heads out of their posteriors.
Now Ram is the only one left running 100% outdated transmissions in some of their HD models (aka all the diesels).

Actually more like being about 5 months behind, GM made the announcement early in Dec 22 and launched the new websites then....lol.

Perhaps too busy then stirring up the shitpot at the time on these boards....lol?

Lol, nah, you may be mistaking me for someone who watches every YooToob video, actually caring about what the next latest update is….

And no one is raving about the (stock) power of the old 7.3 Powerstroke. At least not in the last 15 years or more. That is a poor comparison by which to make a point.

[ognend]

jabres wrote:
Thanks guys for all the input! I am just extremely particular about my vehicles, and hate the thought of needing to carry extra oil at all times!!
Tough decisions on if I trade in, (and fortunately will get every dollar back that I got in it) and get another GM hoping this one was out of the ordinary, or try out a Ford...

People who own the Godzillas seem to be happy with them. It is a nice engine, top of the offering in the gas world right now. Ford even introduced a 6.8L gas engine in the XL trims - so you might want to check that out. I am happy with the 6.6L GM/Chevy gasser, does what I want and does it without a fuss. I am not brand loyal, test drove all three for months and joined all the Facebook groups, followed them to find out all the issues the engines/trannies were having etc. I came from the diesel world (never going back)- the new gassers are potent and do their jobs well. If you think about it - people rave about the 7.3L powerstroke from 20 years ago - well the gassers have double the HP and the same torque but with computer controlled transmissions and very smooth power delivery curves, same level of simplicity (comparably) and cheapness of maintenance. Win-win.

[ognend]

Grit dog wrote:
Whoa, sorry for being a month behind on GMs next years models….lol.
Well good, GM finally pulled their heads out of their posteriors.
Now Ram is the only one left running 100% outdated transmissions in some of their HD models (aka all the diesels).

A lot of people like the 6-sp. It is a known entity, it is paired well with the 6.6L gasser and it is dialed in very well as to where it delivers a smooth power curve and it does it effortlessly. I test drove 10-speeds multiple times (Ford 7.3L gasser) and I went and I test drove the new 10-sp with the 6.6L Chevy. The trannies were constantly shifting and it annoyed the **** out of me. The 6-speed GM trannies are known entities, have been around for years, they are super cheap to replace when they go out. 'Nuff for me. Not every new thing is a good thing for everyone 😉 (how many people have left the diesel world because of CP4 pumps?).

I can even see the point of the 10-sp if you offer different gear ratios but GM is stuck on the 3.73 only whereas Ford offers everything from 3.55 up to 4.30. So what exactly to you get with a 10-sp on the GM gassers? Maybe slightly better gas mileage (although people are reporting pretty similar numbers with the 6-sp) and maybe better towing up the steepest grades. But then I always think to myself - people have been towing up steep grades since 50+ years ago with much less powerful trucks and did it just fine - whether I get to the top of the hill in 15 minutes or 18 minutes - who cares? 😉 Me personally, I am after simplicity and longevity, not the shiny new thing...

[Huntindog]

jabres wrote:
Thanks guys for all the input! I am just extremely particular about my vehicles, and hate the thought of needing to carry extra oil at all times!!
Tough decisions on if I trade in, (and fortunately will get every dollar back that I got in it) and get another GM hoping this one was out of the ordinary, or try out a Ford...

I don't know how you are doing the math but, trading in is NEVER the best financial move. There can be good logical reasons for doing a trade in....But finances isn't one of them.

[CWilson]

Grit dog wrote:
Whoa, sorry for being a month behind on GMs next years models….lol.
Well good, GM finally pulled their heads out of their posteriors.
Now Ram is the only one left running 100% outdated transmissions in some of their HD models (aka all the diesels).

Actually more like being about 5 months behind, GM made the announcement early in Dec 22 and launched the new websites then....lol.

Perhaps too busy then stirring up the shitpot at the time on these boards....lol?

[jabres]

Thanks guys for all the input! I am just extremely particular about my vehicles, and hate the thought of needing to carry extra oil at all times!!
Tough decisions on if I trade in, (and fortunately will get every dollar back that I got in it) and get another GM hoping this one was out of the ordinary, or try out a Ford...

[time2roll]

My 5.4 F150 burns a quart every 3000 like clockwork since brand new. Stopped checking, just drop a quart in every 3000. Gave up on the 3000 mile changes and switched to 10,000 miles. After three quarts in it is almost time for a change. 210,000 will be coming up soon.

Not sure why an extra quart has to be riding around in the truck.

[Grit_dog]

Whoa, sorry for being a month behind on GMs next years models….lol.
Well good, GM finally pulled their heads out of their posteriors.
Now Ram is the only one left running 100% outdated transmissions in some of their HD models (aka all the diesels).

[ognend]

Grit: 2024 has the 10-sp. Personally, I am keeping my '21 6.6L with the 6-sp. Unless you have driven this truck with this engine - the tranny is dialed in perfectly on the 6-sp.

As for oil burning - I think about 10% of the users on the Facebook 6.6L gasser group complain about it. There was a TSB issued by GM in 2020 about it but it only mentioned the 2020 models and was never extended to 2021 etc. I am not sure that this detail matters, given that it is the same engine. My '21 is not consuming oil, for example, however, I have been told by a dealer that some oil consumption is normal. Check your oil regularly like with any other vehicle you have ever owned?

Other than that - I think everyone who has towed/hauled with one of these trucks has been pleasantly surprised, myself included - and I came from an '06 Duramax/Allison and a '16 6.7L Powerstroke. Like some people here seem to have a visceral hate of GM - after owning the Powerstroke - I now have a deep disdain for Ford's quality control. If you are looking into gassers, Ford's 7.3L Godzilla sounds like a better/bigger/stronger engine but if you have ever been burned by owning a Ford that had all sorts of problems, well, the GM is the ticket. BTW, if you are worried about oil consumption - this is the only "problem" with these engines. Spend some time on Facebook on the 7.3L Godzilla groups to see the litany of issues they have been having with everything from spark plugs to transmissions to.... Same with the 6.4L HEMIs - the 8-sp ZF tranny may sound great but then ask about the lifter issues. I conducted a survey on the 6.4L HEMI FB group when I was doing research on the gassers and 11% of the owners on the group reported a lifter problem early into the truck's ownership.

[CWilson]

Dadoffourgirls wrote:

Grit dog wrote:
...
Oh, that’s cool. Is there a mid year update? Or is the 2023 HD model specs wrong when it lists the 6 speed as standard (w/ gas engine) and 10 speed an optional but only with the diesel? ...

2023 HD is last year, not a mid year update - a 2024 HD!

They have been building 2024 for over a month!

The 2024 6.6 gas gets the Allison 10L1000 as standard.

[Dadoffourgirls]

Grit dog wrote:
...
Oh, that’s cool. Is there a mid year update? Or is the 2023 HD model specs wrong when it lists the 6 speed as standard (w/ gas engine) and 10 speed an optional but only with the diesel? ...

2023 HD is last year, not a mid year update - a 2024 HD!

They have been building 2024 for over a month!

[Grit_dog]

^They were probably uninformed buyers who realized they could have had more power and a better transmission for the same money! Lol

[CWilson]

Perhaps you have joined GMRRRD program not by your choice but theirs?
(General Motors Real World Research and Development)

When GM came out with the 3rd gen Vortec 5300 LM7 in 1999, which was in Silverado 1500s, Burbs and Yukons, etc, it was plagued with a cold start piston slap. Sounded like **** at cold startup, like it was getting ready to throw a rod. GM claimed it was "normal". By 2001 model year they had corrected it even though it was normal. I owned a 99 Silverado that had it and took it to over 280,000 on the ticker before I sold it, but it always had that cold start knock and it was about as annoying as possible but to me a new engine sounding like its going to puke a rod is not normal LOL.

The point is with a new engine like the 6.6 you are rolling the dice and GM is notorius for claiming things are "normal" as are all the manufacturers. Using a quart of oil in 1000 miles is in no way normal IMO, especially on a $60K+ truck LOL.

Perhaps that's one of the reasons why I see a lot of 2020/21 ultra low mileage 6.6 L8T trucks on the dealer lots around here.