In my 01 Silverado HD 6.0 auto, at 102k/mi now, I drove a severe service 2 - 5 mile lightly loaded city trips several times per day for six years at my previous job. It would barely warm by the time I reached my destination. Trucks lives in north Florida, see temps from 25°F - 100°F, and gets driven fairly slowly to get its best mileage (like 13- 14mpg).
In a few cases about 3 - 5 years ago, I went somewhat beyond, like 1 to 2k more, than the truck's OLM, which said 4800 - 5100 miles consistently. On a 3 or 4 runs the oil went almost 2 qts low during the OCI in a 6 qt CC from not bothering to top up.
After getting a new job that's 15 miles away and doesn't require short trip driving, several problems seem to linger on that are likely motor oil related...
There is consumption, about 1 qt every 4 - 5 fillups, or 1200-1600 miles.
It looks like the PCV scavenging of the CC causes some of the (vaporized) motor oil to not only burn in the cylinders but get into the intake manifold and ports and leave varnish/ gum / resin deposits on the throttle body that can make it stick shut at idle.
Probably the piston rings are allowing more blowby than they should and that's at least somewhat responsible for the LS's oil consumption.
I have used Berryman's carb cleaner on the throttle body maybe 4 different times, ran seafoam thru the intake manifold twice, replaced the pcv valve twice, switched to high mileage oil about 20k/mi ago, and for the last 10k miles ran MMO in the gas (definitely reduced light pinging, made idle smooth, and quieted the fuel pump down).
Could a lower NOACK rating oil fix the consumption issue, or should I resort to a running a cleaner in the CC to maybe free up the rings more?
In a few cases about 3 - 5 years ago, I went somewhat beyond, like 1 to 2k more, than the truck's OLM, which said 4800 - 5100 miles consistently. On a 3 or 4 runs the oil went almost 2 qts low during the OCI in a 6 qt CC from not bothering to top up.
After getting a new job that's 15 miles away and doesn't require short trip driving, several problems seem to linger on that are likely motor oil related...
There is consumption, about 1 qt every 4 - 5 fillups, or 1200-1600 miles.
It looks like the PCV scavenging of the CC causes some of the (vaporized) motor oil to not only burn in the cylinders but get into the intake manifold and ports and leave varnish/ gum / resin deposits on the throttle body that can make it stick shut at idle.
Probably the piston rings are allowing more blowby than they should and that's at least somewhat responsible for the LS's oil consumption.
I have used Berryman's carb cleaner on the throttle body maybe 4 different times, ran seafoam thru the intake manifold twice, replaced the pcv valve twice, switched to high mileage oil about 20k/mi ago, and for the last 10k miles ran MMO in the gas (definitely reduced light pinging, made idle smooth, and quieted the fuel pump down).
Could a lower NOACK rating oil fix the consumption issue, or should I resort to a running a cleaner in the CC to maybe free up the rings more?