07Suburban burning oil?

My 07 Suburban turned 30K miles and now appears to burn about 2 qts of oil every 3-4,000 miles. No leaks, blue smoke. Dealership tells me it is normal for this engine??

If you don’t believe the dealership, pay for an engine compression and leakdown test to determine where the engine oil is exiting the vehicle at.

Also, make sure you change the PCV valve on the truck, as if that is stuck, it can cause oil to be burned.

Are you running the truck under any extreme driving conditions?
An example is really high highway speed while towing an 8k lbs trailer all the time.

BC.

While I would not enjoy having a car burn that much oil, be prepared for the automakers to have a different view. Most (or all) manufactures consider burning a quart every 1000 miles as the threshold where they’ll spend warranty dollars looking into it.

Since you’re only burning a quart every 1500-2000 miles, don’t expect any help from Chevy.

The dealership wants to do a “consumption test”. From what I have read, I do not believe much will come from that. It is driven daily, mostly city by my wife. Used it to tow a 4K lb trailer 4 times only for short drives.
Can the dealership do a compression test?

A quart every 2000 miles is NOTHING…What kind of oil do you use??

Synthetic blend, never owned anything that needed oil that frequently. Not leaking anywhere.

It may be considered normal by many but a quart every 1500-2000 miles is excessive in my book.
Since it’s not leaking this means it’s burning it; either past the valve seals or iston rings.

Buy the vehicle new, as in 4 or 5 miles, or was it a returned lease or dealer demo?
How often is the oil changed?
What type of driving do you predomninantly do; mostly city/stop and go or highway?

Bought new, used same dealership for oil changes that were done every 4,500 miles on average. Driven daily, 85% city. Switched to synthetic blend before it had 10k miles on it.

My feeling (and this is a semi-educated guess) is that maybe the 4500 miles oil change intervals are frequent enough based on the 85% city ratio and assuming moderately severe environmental conditions.

This can lead to the piston rings (especially the oil control rings)seizing in the ring lands. The oil control (wiper rings) are meant to be very free in movement and any sludging at all can prevent free movement. When the rings are sludged up a bit they may not conform to the shape of the cylinder wall and will not thoroughly wipe the cylinder wall of oil when the piston is on the downstroke.

One of my sisters-in-law has a Trailblazer and with her type of driving the oil should be changed every 2k miles or 3 months. The driving habits are very severe in nature and seldom does the engine even get up to operating temperature.
Of course, she refuses to change it that frequently.

A leakdown test may (?) shed some light on ring condition but even that test is not a slam dunk in determing the cause. It helps is about the best that can be said.