Duramax Engine Oil

[COGrandDes]

I completely understand this. I too have had dealer issues. Each dealership has so many diesel techs. I have made it a point to reach out and talk to them. I also have changed dealerships from my purchasing one as they were a high volume push them through dealer. I am satisfied with my dealer and the relationship I have with the service guy and the mechanics.

Bill

I worked at several of the GM dealers many years ago but would never take my vehicle to them today for many reasons. The quality and talent is just not there like it used to be. I do all my own maintenance and even have given up "free" oil changes and maintenance to do things myself. My salesman was surprised when I told him in March that I would not be back to take advantage of my first free service on my new truck. Told them they would never see me again unless there was a warranty issue that needed to be fixed. Do the work yourself, save the money, and check things over rather than depending on others who don't really care about your vehicle.

I have used Rotella and Amsoil.....many good brands out there. Pick one and stay with it.

[Patman]

I also do most of my servicing and have strictly used Rotella T6 Full Synthetic in my 2016 3500 Duramax. Actually I use it in my Yamaha SXS as well. Real good stuff! For the Allison, TES-295 synthetic transmission oil is highly reccomended.

[Scott'n'Wendy]

Any of the well known reputable oils will be fine. Do regular changes and they will all do the job.
That said, I use Mobil and Amzoil 5-40 synthetic. IMO, the biggest concern is a good filter. I use Fleetguard, Mobil 1 and Amzoil synthetic filters.

[jmbopp]

My brother runs 5 or 6 tandem trucks, a backhoe, Cat front end loader, and 2 Diesel pickups. He buys Rotella in 55 gallon drums for everything.

[Markb777]

I change my own and use Mobil 1 Turbo Diesel 5W-40. I spend a lot of time in cold weather during the winter and prefer the 5W over the 15W. I use the OEM GMC oil filter. The GMC diesel supplement shows 5W-40 as an approved viscosity.

[JohnJD]

I have been using Rotella T6 when I can find it in my 2019 HD2500. It has been difficult to get since covid, so the last 2 oil changes have been Mobil Delvac 1300. I use the same AC delco filter the truck came with.

[LawDawg]

Amsoil Signature 5W-40 with Amsoil filters for my 2019. I have purchased the Amsoil full flow/bypass (1 micron) filtration kit but not installed it yet. Filters matter a lot.....Amsoil, Mobile-1, and K&N are my top choices....please don't use Fram with their glued paper construction under any circumstance!

[Malco1]

Another question about the Chevy Duramax Diesel. I'm going to start doing my own oil changes and of course there's a variety of synthetic 15W-40 choices out there. Our trips always include towing around or through Texas which has been brutally hot in recent years. What brand of oil and filters are you guys using these days? Appreciate your advice.

Don't forget to use oil is specially formulated for diesel engines. The oil is part of the cooling system. In my youth I once changed the oil in my diesel car and used regular oil. That resulted in a blown head gasket, so I saved a few dollars on oil and it cost me several hundred for the repair.

[jasonPlegrand]

Rotella T-6 here as well. The next most important thing to a quality oil filter is to change fuel filters often. I was told by my mechanic it’s cheap insurance on these diesels to change fuel filters WELL before the owners manual says to.

[huntindog]

Rotella T-6 here as well. The next most important thing to a quality oil filter is to change fuel filters often. I was told by my mechanic it’s cheap insurance on these diesels to change fuel filters WELL before the owners manual says to.

Actually it is a waste of money. A used filter actually filters better than a new filter, as it gets dirty it filters smaller particles. If you are concerned about it plugging up, carry the new one with you. If you get a fill of dirty fuel, a newly installed filter will plug up almost as fast as a used one. So if you have a new one on hand, you may be able to install it and drive far enough to get to a service center. I know my Dmax filter minder system actually monitors the restriction in the oil and fuel filters and calculates the remaining percentage of life left. I am sure the OBs do similar. btw, I do not bother carrying a spare with me. No issues since I went diesel in 2000