I asked this in the 2007 - 2013 (GMT900) forum, but not much response.

I'm sure it isn't a major deal, but I'd like some opinions. I am getting ready to do another oil change on my 2007 Silverado 1500 4.8L. It has very LOW Mileage. 28,000 miles. It was my Father-In-Law's truck. He bought it new in 2007, had a stroke 3 months later, drove it very little for the next 15 years (about 1,000 miles per year); passed away in 2022; I've had it since.

Anyway.... here's the question/situation. We sold my wife's Toyota Rav4. It used 0w-20 oil. I have 6 quarts of unopened Mobil 1 0w-20 oil with no vehicle for it. The silverado uses 5w-30 oil. I DON'T WANT to simply use the 0w-20 oil. But, if the Silverado uses 6 quarts of oil, would it be ok to use 5 quarts of mobil 1 5w-30 and 1 quart of mobil 1 0w-20 oil. And do this repeatedly for the next 5 oil changes until the 0w-20 oil is gone? That's a 16% 0w-20 vs 84% 5w-30 capacity. Same additive package in both oils from Mobil 1. The combined viscosity SHOULD be around a 4.2w-28.4 . (Or rounded off...... 4w-28 )

I do oil changes every 5,000 miles OR 1 year; WHICHEVER comes first. The oil change meter has never gotten below 40% end of life.

I can't think of any other use for the 0w-20 oil. For liability reasons, the auto parts stores won't exchange it for 5w-30. I don't really know anyone who uses 0w-20 that wants to buy it. And I really don't want to take $50+ worth of oil and throw it away. At the same time, not really worth my time to try and advertise, sell, and ship it either. It's only 6 quarts.

Any thoughts??? I can't really think of any other uses for the 0w-20. My lawn mower is battery and my snow blower uses 2-stroke mix/gas
Thanks
Mike

 

I wonder if a 0-20 and a 10-40 would equal a 5-30?? I know there are folks here that can answer this with some knowledge/science, lets see what gets posted in the next week or two

 

Yea, not trying to do anything fancy or any type of hack. Just got 6 quarts of new-unopened 0w-20 and no vehicle for it. I'm 95.438589302% sure that it will be fine mixing. It would be different if I were mixing 50/50 between the 0w-20 and 5w-30, but I'm just reducing the normal 6qt 5w-30 to 5 qt and 1 qt of 0w-20. Definitely hoping for some first hand feedback. I have 3 vehicles that use 5w-30 oil. It's not that I don't have enough. I have plenty. Just trying to find a use for the 0w-20.
Thanks
mike

 

I believe I've made a decent decision. At least the best I can rationalize. I feel there's no problem using 1qt of the 0w-20 with 5qt of 5w-30, but I've decided a different route.

I will use the 6 qt of mobil 1 0w-20 as an "Engine Flush". I am NOT A FAN of "Chemical Engine Flushes". NONE of them. A vehicle would have to be in really rough shape for me to ever think to use chemical engine flushes. But over the last 50 years of driving and having many vehicles, I do perform "engine flushes". But I do it ONLY with motor oil. Basically like a normal oil change; warm up the vehicle; drain the oil; LEAVE THE OLD oil filter in place...... Fill back up with the cheapest (CORRECT TYPE) of motor oil - E.g. SuperTech from walmart; run the vehicle (Idle, not driving or revving) for about 15 minutes; then drain all the oil AND the oil filter. New filter and GOOD oil.

I do this with all my vehicles that are NOT still under warranty. And being I keep my vehicles for many years, I usually do this flush about once every 5 or 6 oil changes. I've had many vehicles that have done more than 200,000 miles. And this method only costs an extra $16 or so. (That's the cost of a 5 qt bottle of SuperTech synthetic oil at walmart).

I've only had the Silverado for a couple of years (since my father-in-law passed away), and it only has 28,000 miles, but it is a 2007. That's going on 19 years. I've done a few oil changes in the short time I've had it, but it can't hurt to flush it out. And it won't hurt using the 0w-20 oil as a flush because the engine won't be under any massive stress or high RPM's. The reason we do engine oil changes when the engine oil is warm, is to get as much of the impurities, metal particles, or other contaminants to be suspended IN the oil so it will flow out when you pull the drain plug. Unfortunately, a lot of it still remains; and it stays there and accumulates even more over the next 5000 miles or so before the next oil change. With this flush method, it's been shown to remove approximately 20-25% MORE than the original 1 time oil change. The chemical method of "Engine Flush" obviously is intended to get much more. Unfortunately, on older vehicles or vehicles that haven't been really well cared for, the chemical flush can break up large pieces of sludge and hurt the oil pump. It can also affect seals, gaskets, etc.... The motor oil method is 100% safe. Most people don't do it because they think it costs a lot. E.g. $75 oil change TWICE. If you do your own oil change, you can use cheap SuperTech oil and it doesn't cost anything. Just use similar oil. I.e. if your car uses synthetic, use synthetic for the flush too.

Anyway.... I hadn't thought about doing an engine flush because the truck only has 28,000 miles. But after realizing that the silverado is almost 19 years old...... I think it would be a good idea and make great use of the 0w-20 oil I have no vehicle for.
Thanks for listening
Mike