MachWun

New phenomenon. Several MFGs (possibly all) have an acceptable amount of oil loss. So now we need an accurate oil level gauge in vehicles just like the gas gauge since we will need to add oil every 3 tanks of gas. I am 6' 4" and can't fill my oil without a step ladder. This will suck in the Winter!

Lol, 1. They did not do any of this except add oil. 2. By what is written, I have a problem. I should have used half of the oil I did. And the last tech they told me was a 'master cetified GM technician' or something like that. Claimed there is so few in the country. "He is so ****** about following process."

No Smoke. And no evidence of it at the front of the RV.

I have a 2020 Sierra 2500HD Denali with the Gasoline engine. I did not have a problem or wasn't aware of one, until about a year ago. Low oil light came about for the first time. It took almost 3 quarts to get it into the cross hatch area on the dipstick. Later I discovered that the dealership only put in 6 quarts of oil (when truck had about 19,000 miles). Since this time, I've noticed the truck consuming oil, a good amount, between oil changes. About 1 quart per 1,000. I have never had to add oil between changes. The dealer checked it and found no leaks anywhere, topped off the oil, and sent me on my way. I asked for an oil consumption test. They incorrectly performed an oil consumption test the first time. The second time, fresh oil change, returned at 2,000 miles, and down 1.5 quarts of oil. Returned again after 1500 miles and down another quart. This is per the tech's documentation. BUT, on the sheet, it is noted that TWO quarts of oil were used (qty 2 of part number 88865926). The tech goes on to state, "the vehicle does show signs of being used to tow," and "per doc ID 6143939 this vehicle is consuming the normal amount of oil of quart per every thousand miles, this document also states it is normal for the vehicle to consume more than a quart every thousand miles when the vehicle is being used for towing or for highway usage due to higher than normal engine loads." I have an RV and is the reason for buying the 2500 (who buys a 2500HD for pleasure - i.e., no hauling??). HOWEVER, I had NOT towed anything nor any load beyond me and maybe my 120 pound son for 5 months before this latest oil consumption test. No one asked me what driving I had been doing. I just recently returned from vacation with my RV. I drove about 4,000 miles and about 3,000 miles was towing the RV (about 11,500 lbs). Truck consumed 12 quarts of oil. 12!!! Prior to reaching 19,000 miles, I drove the RV several times including long trips and the low oil never went off. BTW, no one is willing to scope the engine, pull the throttle body, nor check the PCV system.

I've read through a lot of this long thread and am feel a lot of dread. I have a 2020 GMC Sierra 2500 Denali. The dealer put 6 quarts in the engine at 19,000 and I have since started burning oil. First time I took it in they checked for leaks (found none) and gave it back saying come back in 1,000 miles. Of course, once GM got involved, the dealer realized they did not conduct a proper oil consumption test. I am in the middle of one now and can see a huge shift in 'cover you ***' type of documentation. Likely because GM has contacted them about it. Read the last order and you can smell the BS. First return to dealer it was barely on the dipstick. Added 1.5 quarts (so they claim) Second return is was not on the dipstick. Added 1 quart. Noted evidence of towing. **NO STUFF!! Who drives a 2500 for pleasure? But I have not towed since early Fall, 1,000's of miles before the last oil change and consumption test. They state on the order that 1 quart per 1,000 miles is acceptable. Assuming an oil change at 5,000 miles, and I lose 62.5% of my oil?? From driving 60% highway / 40% city? Note the order has a quantity of 2 for quarts of oil. Why 2 if they only used 1? I have had 4 Chevy and GMC pickups plus 7 other GM vehicles. If nothing further is done, I likely need to sell this very expensive truck. If I do, it will be my very last GM product ever.

Never had a car that burned up any oil. Routinely checked all my fluids. There has been a couple of changes though, right or wrong, the MFG's have put so much tech into the vehicle, people are used to it telling them what to do: 1. Tech Miles until empty % brake life remaining % left before next oil change Check tire pressure etc. 2. Size, the 2500 is a big vehicle, you need a step stool to reach over and in the engine compartment to check the oil and other fluids. When you make it more challenging, people do it less. 3. In general, the majority of drivers are ignorant. Most do not understand the basics of what makes a car work. 4. Dip stick, it is almost useless. It has a cross hatched area on it. Even when there is oil in the cross hatch, you could be down 2 quarts. The old "low" or "add" on the dipstick is gone and there is no definition in the book that I am aware of to explain how dire the situation can be. (see #1 as it tangentially applies here). I am handicapped and cannot check with ease. And since 'full service stations' do not exist anymore, you can be sured I am going to figure out how I can have it checked periodically... especially from the get go on my next truck. Because I doubt the dealer nor GM is going to support me here and thus, I see myself dumping this one.

So, contacted GM. That bore no fruit. The assistance is to contact the dealer to express my concern (I can do that) and schedule an appointment (I can do that to). What I found is a service bulletin that say to change the oil to start an oil consumption test and then routinely complete a log they attached to the bulletin. Dealer did not change the oil and told me to come back in 2000 miles for them to check the oil. Hmm, the quantity of oil in the engine is unknown since I added three based on the dip stick (not very scientific). I would be well past my oil change interval (not good) and, they did not check my service detalis. If they had, they would have noticed they only puy 6 quarts in at the last oil change. Unless something drastic changes, it is looking like I will be selling this truck. And if I do, will be my last GMC. Loyalty out the window. Been a lifelong GM customer, buying a new one sometimes in 2 years.

I have the same problem. Plus, the last oil change, the dealer only put in 6 qts. I didn't notice it on the receipt. Big surprise, awhile later, low oil light came on. Took 3 quarts to bring it to full. Took it to the dealer. They gave it back saying they will do an oil consumption test and to bring it back in 2,000 miles. No need for an oil change since it is full. What the bleep!! According to the service bulletin (yes, there is one) you must change the oil first. Down at least 2 quarts or more for 4,000 miles and and this is the response. BTW, don't contact GM, they do not add any value in solving the problem. Lifelong GM customer. Think this is my last.

I have a 2020 Denali 2500HD. I had the low oil light come on at least once before. Around 12,000 miles and again around 17,000. But I explained it away because I was towing my RV about 1800 miles on the one occasion. Well, I have 23,000 now, about 2400 since my last oil change. Full synthetic. And it took 3 quarts to get it squarely in the cross hatch on the dip stick. No oil on the ground. This is an expensive truck so dumping it is a lousy choice after 2 years.