Excessive oil consumption - at least 1qt per 1K miles sometimes more. Chevy eventually fixed this under warranty after proving out the consumption. Chevy corporate is aware of this problem in these trucks and has not only written it up, but has designed a fix for it, dealer states Chevy Corp declined to issue a recall because it's a $1600 repair. The issue is two-fold. Something to do with the valves not sealing correctly and oil in the oil plan splashing up onto the cylinder walls faster than the rings can remove it. When my vehicle was repaired, they did some work to the valve train, replaced fouled spark plugs and added some type of baffle to the oil pan. Fix improved power, fuel consumption and reduced oil consumptions to normal levels. Truck now runs like new. If you are experiencing this go to Chevy and demand the fix. You'll need to prove the oil consumption either through oil change logs, or as I did - which was to do an oil change at the dealer, have the oil plugs sealed by the dealer, then drive it 6,000 miles - having the dealer refill the oil when low to track consumption. They won't want to fix this because it's so expensive but demand the repair under the warranty.

- Kirkland, WA, USA

Vehicle has excessive oil consumption, using more than 1 quart of oil every 2K miles. I purchased the vehicle at a GM dealership with 67K miles on it. They told me it was just serviced, and the dipstick showed to be at the full line with clean oil. About 4K miles later the low engine oil light came on. The engine oil life indicator said it had 49% life left. I checked the oil level and found it was more than 2 quarts low. I have researched this and found that GM is either unable or unwilling to repair. I will contact the selling dealer for the record.

- Glendale, AZ, USA

I have a 2007 Suburban that consumes approx 1 qt of oil every 800 miles. At 1200 miles/qt the dealer told me this was "normal consumption". I went to another dealer that confirmed the 800 miles/qt and is installing new pistons and rings next week. Apparently this is not a fix but should help with consumption until a permanent fix is made by GM.

- Binghamton, NY, USA

The engine consumes approx 1 quart of oil every 1700 miles. There is no oil leaking under the vehicle.

- Los Gatos, CA, USA

I am seeing an excessive oil consumption issue with my 2007 Chevy Suburban. From my measure it is consuming 4 1/2 qts of oil per 3000 miles. The dealer acknowledged that this is a "known" issue but didn't perform any repairs. I am instead performing an oil consumption test. That's fine but I now have a family vehicle that I cant trust for anticipation of engine failure/lock up or worse engine burn up or fire from a low oil condition.

- Caledonia, WI, USA

Engine consuming oil.

- Glenview, IL, USA

The contact owns a 2007 Chevrolet Suburban 2500. The contact took her vehicle to the dealer because it was underpowered. The vehicle stalled at intersections and while merging into traffic at 15 mph. She heard strange noises coming from the engine compartment. The dealer was unable to diagnose the cause of failure for five weeks. Chevrolet sent a representative to inspect the failure and stated that the vehicle was designed to drive in that manner. The service manager and the dealer owner acknowledged the failure, but the district manager was reluctant and informed the dealer to stop repairing the vehicle. The contact drove the vehicle back to her residence where it currently remains. The current mileage was 3,000 and failure mileage was 2,500.

- Lake Havasu City, AZ, USA

: the contact stated while driving 20 mph, the check engine and the traction control light illuminated constantly. The engine then lost the majority of power and would not accelerate. The vehicle was moved to the side of the road, and was shut off. The vehicle was restarted after 10 minutes and driven to a residence. The vehicle was taken to a service dealer, who was unable to determine the problem. The manufacturer was also notified.

- Sequim, WA, USA