Vortec 5.7l oil consumption.

[RayHardesty187]

My stance on it is, change it every 3k and run the piss out of it. Mines 23 years old! If it was 2-3 years old I might send off for analysis or if it was a 10k built race motor same thing. It's and old truck, here they say "it's just an old camp truck" that's the excuse to run it with as little maintenance as possible, don't wanna use beer money for oil and such inconveniences lol

Stole my words right outta my mouth. Its not like a replacement motor is 10 grand. Its a waste for me. I've got better things to do. But hey thats jus me.

 

[Schurkey]

You're almost certainly changing oil 2--3--4 times as often as you need to.

I have better things to do than change oil uselessly.

Don't get me started on the benefits of an aftermarket bypass oil filter, which pretty-much means the oil is kept clean for 30--50+ thousand miles; just change the full-flow filter now and then, and keep the oil level topped-off as needed.

 

[Pinger]

Having established that my Vortec is thirstier on oil than it should be, how is it getting into the cylinder?

Hone marks still on bore (but can't exclude damaged oil control rings).
Valve guides - is there enough oil pooled around them during running to cause high oil consumption?
From the crankcase to the inlet ports via leaking inlet manifold gasket or cracked manifold - plausible?

 

[Schurkey]

Any or all of the things you mentioned.

The first thing to check is the PCV system. Oil in the hoses?

How old are the valve stem seals? Easy enough to replace, and not horribly expensive. While the springs are off, wiggle the valve stems in the guides (don't drop a valve!) If the guides are wiped, you know to pull the heads for valve work.

Warm the engine, pull the plugs, squirt two ounces of "Top Engine Cleaner" into the cylinders. Turn the crank a full revolution (plugs OUT), then let the stuff soak the rings overnight. Next day, crank the engine to assure no hydro-lock, put the plugs back in, fire the engine, warm it up, and repeat.

All of this is useless if the rings are actually damaged, cylinders scored, etc. But it takes care of the simple issues.

 

[Crookedaxle]

Wife's Envoy is easy, I just do it when I'm told to by the DIC.

You may want to re-think that one. The wife's 2012 3.6L Traverse was kicked to the curb at 131,000 miles with the dreaded timing chain stretch issue they're known for. I was changing oil (semi-synthetic) at the stealership when there was 20-30 percent life left on the OLM. No short trips, minimal idling etc. etc. Knowing what I know now, I'd run full synthetic and change it religiously at 5,000 miles and ignore the OLM altogether. You go way over just one time on an oil change with that motor and the timing chain is destroyed. And I never went over 10,000 miles. This is what GDI does to your oil. The GM Technical Service Bulletin that recommended you run only full synthetic instead of semi synthetic never reaches you unless you seek it out and evidently the local stealership that was supplying the semi synthetic never bothered to read it either. There should be a class action lawsuit on the 3.6L motor. I like my older General Motors vehicles but won't touch anything new (Government Motors) ever again.

 

[Crookedaxle]

I just change my oil every 3 thousand miles, and never waste money on some so-called scientist playing in my old oil.

Easy to err on the side of caution and spend the extra bucks with one small personal vehicle. If you had that mentality with a fleet of semis or excavation equipment you'd be bankrupt in a short time. There is a very real need for oil analysis in this world. It's also used for power steering fluid, hydraulic oil, Caitlyn Jenner fluid etc. etc. and they're used just as much in the industrial world.

 

[Supercharged111]

You may want to re-think that one. The wife's 2012 3.5L Traverse was kicked to the curb at 131,000 miles with the dreaded timing chain stretch issue they're known for. I was changing oil (semi-synthetic) at the stealership when there was 20-30 percent life left on the OLM. No short trips, minimal idling etc. etc. Knowing what I know now, I'd run full synthetic and change it religiously at 5,000 miles and ignore the OLM altogether. You go way over just one time on an oil change with that motor and the timing chain is destroyed. And I never went over 10,000 miles. This is what GDI does to your oil. The GM Technical Service Bulletin that recommended you run only full synthetic instead of semi synthetic never reaches you unless you seek it out and evidently the local stealership that was supplying the semi synthetic never bothered to read it either. There should be a class action lawsuit on the 3.5L motor. I like my older General Motors vehicles but won't touch anything new (Government Motors) ever again.

I know about those motors. She has the LH6 5.3 V8 and it gets full synthetic every time. Just the other day I put a notebook in there and documented the date and mileage of the change as I am curious approximately how far it lets it go.

 

[Crookedaxle]

I know about those motors. She has the LH6 5.3 V8 and it gets full synthetic every time. Just the other day I put a notebook in there and documented the date and mileage of the change as I am curious approximately how far it lets it go.

What year Envoy???

EDIT:

Crap, I was thinking Acadia, not Envoy. I also edited my post to show 3.6L, not 3.5L.

 

[Supercharged111]

What year Envoy???

EDIT:

Crap, I was thinking Acadia, not Envoy. I also edited my post to show 3.6L, not 3.5L.

Yeah, those motors had a software update to shorten the OCI. I originally wanted an Acadia, but was partly scared off by the timing chain issues and the price tag. Found this Envoy with 63k on it back in 2016 and jumped on it.

 

[Crookedaxle]

Yeah, those motors had a software update to shorten the OCI.

Also a Technical Service Bulletin if I remember correctly so if you weren't looking for it you're not going to be aware of it.