I have always burned excessive oil in my truck. I can drive 300 miles and need to add a quart. I just did a full 90,000 mile tune-up and was shocked to see how degraded the plugs were. The tips were all black and worn. The gap should be .060 and these eight ranged from .010 to .090. Interesting for factory installed plugs. That kind of goes along with all the oil I am burning though. I have never seen a leak in my garage. It blows me away that a truck that I love so much can be such a pain in the ass. The dealer has always denied that there is a problem. They blame it on my heavy trailering and four wheeling. I thought that is what trucks are for. I can't imagine ever buying a Ford or Dodge though, let alone a foreign truck.

I just purchased this truck,I have always owned GM trucks. You all must realize they are not "AMERICAN MADE MACHINES" anymore. The quality has been substandard since the NAFTA agreement of the US to be able to produce substandard quality with substandard metals built by substandard laborers with a real macho look and great paint and easy financing.I was burning a quart every 500 to 600 miles . I tried an oil cleaner additive but to no avail.No smoke no blow by no dirty plugs no evidence.I hung a 180 thermostat in to cool down the motor which intern lessens expansion of the metals.Now a quart every 1200 miles so only paying 9k for an 01 4wd 2500 HD in xlnt cond it's cheaper than the right fix. A few quarts are cheaper than a replacement engine.I am an ASE certified mech 30 years now. Good Luck

8.1 L oil consumption is probably 'normal" under any official guidelines ( work in engine service) but have been loosing between changes from new. Thought the rings might have needed to seat but am well beyond time-frame for that. I am going to get the problem on record before warranty end but I expect GM and our dealer will make it right. Rant and gripe all you want but unless you have incurred a repair expense due to this I don't see any point in becoming inflamed. It might be more productive to provide consumption info the dealer needs. It seems unlikely that GM or its dealers will be inclined to burn customers of high end engine powered product.

Getting excessive oil consumption - 3 qts. in 3000 miles. I think that GM is full of crap. I have taken this truck to the dealership for two consecutive oil consumption tests. First they installed longer intake manifold bolts, that fixed nothing. They acted like they knew nothing, then after second test, they gave me the TSB saying thats the way it is and excessive oil consumption is normal. Then when i found all of these other complaints on the internet, I realized they were just yanking my chain. What a terrible way to do business. I will sell this truck, and i will not ever buy any GM product again.

Started noticing excessive oil consumption with my Duramax diesel just about like the other people with complaints about oil consumption that they have and I am being told the same nonsense about this is expected. I asked the dealer if he would really expect a new PU buyer to buy a Duramax equipped PU from him if he told them that they could expect to add 1-2 quarts between oil changes and he kind of looked at me like he didn't see a problem with excessive oil consumption. The dealership also has me doing the same nonsensical recording of my mileage, engine hours, oil consumption, etc. etc. just like the other owners. Numbers on paper do not get the problem fixed. I have also talked to other Duramax owners and they don't seem to have this problem. Just emailed Chevrolet today so I am kind of anxious to see what kind of runaround they will give me too. I find it interesting that both gasoline and diesel engines are having the same problem in the 2001 models.

This is an update from my previous complaint. This truck has burned oil from day one. I went to ohio about two weeks ago, I checked the oil after 450 miles and this piece of junk burned one full quart of oil. One quart of oil in 450 miles!!!! And there is not one drop on my garage floor, so it must be going out the tailpipe. The report said 800,000 vehicles with defective engines, that's a lot of pollution. My problem is just getting worse, I hope the class action lawsuit happens soon. I top off my oil every week, that is very sad for a vehicle 3 yrs. old!!!

Took a 300 mile trip and the "Check Engine Oil" message appeared on the message center. I checked the oil level to find a hint of oil showing up on the dip stick. Down 1.5 quarts. I had 2000 miles on the vehicle since the last oil change. Going to the dealer tomorrow. Awaiting information regarding a class action lawsuit regarding 5.3 L and larger engines. GM may have a service bulletin pertaining to engine knock/misfiring and carbon buildup on pistons possibly due to redisigned pistons and oil blow by. A co-worker of mine has a friend that is involved in the lawsuit. Will update soon if I can get solid information.

I have a 2001 Silverado 3500 with a 6.0L engine. Before my truck tells me it's time to change the oil, it tells me to check engine oil level. I recently went on a trip of 900 miles, I topped off the oil before leaving, and when I returned I had about 1/8 of an inch of oil on the end of the dipstick. Down 1 1/2 quarts (guessing) This was after my warranty expired, about 40,000 miles. I called the dealer about this at about 20,000 miles and they said 1 quart in 3,000 miles was normal oil consumption. I used to own a GMC 3500 with a 454 (non vortec). I NEVER had to add oil not even at 140,000 miles. I would love to see a class action suit against GM about these engine problems.

I noticed the NEW 8.1 Liter (496) engine was using oil when the oil light came on during a trek into rural Oklahoma. Luckily I had someone else get me some oil so I wouldn't damage the engine. I immediately took the truck back to the dealer the following buisness day. Reliable Chevrolet in Richardson Texas took a look at it and couldn't find an oil leak, engine still clean as a whistle. Maybe they didn't fill it up when I bought it? Who checks on a new car, right? Dealer wanted to start an oil consumption test on the truck. I played along not knowing what to expect. In less than 1000 miles it used a quart of oil. Contacted the dealer, they said it was within GMC spec's. They said I had to use more than a quart per 100 gallons of fuel in order for it to be out of spec's. The GM Customer Service 1-800-222-1020 GM number is totally useless, that the dealer will ask you to call for assistance. They send you back and forth all the while never telling you anything. Now I'm having to go through the trouble of doing all this research and callling people and raising hell just because GM doesn't want to fix a PCV valve problem that they know exist. GM rep's told me they knew what the problem was but they can't fix it because it's not an official recall item or my oil problem isn't bad enough yet?

GM just lost a customer for life. They have treated me unfairly and took a lot of my money. If you are thinking about buying a car or big truck, specifically the "Chevy Silverado 2500 HD - TRUCK OF THE YEAR" ..yeah right... stay very far away from GM. This is my newly formed opinion as I have always thought of myself as a Chevy person. Next time I'll buy a Ford or Toyota. The saga continues... I'll provide updates or further gripes as they occur. Happy car hunting folks. Remember, just say no to GM.