Oil Life Shows 40% on New 2500HD

unit · April 3, 2020

I picked up my 2020 Silverado 2500HD with the Duramax engine on March 2nd. I have just over 800 miles on it and it's showing 40% oil life on the dash. If I bring up vehicle diagnostics on the My Chevrolet phone app, it will alternate between 89% and 40%. That is it may show 40% on the app when first checked and then show 89% if I update the app display. I know 40% is wrong and I'm planning on changing both oil and oil filter at 1K just so I can zero out the oil life monitor. The truck has a July 2019 build date and had 74 miles on it when I picked it up. Any ideas why this is happening? It's just kind of strange but will probably be OK after the oil is changed and the oil life is zeroed out the first time.

Edited April 3, 2020 by unit
Fixed working.

Thankful · April 3, 2020

I read several years ago, somewhere, that the oil life monitor utilizes time more than anything else. It's possible, since your truck was built nearly a year ago that the oil life is down to 40%. I don't know why it would alternate between 40% and 89%. Since you're planning on changing it at 1,000 miles, I wouldn't worry about it. When you change it, reset it, and everything will be fine.

ShotgunZ71 · April 3, 2020

You can also just reset the OLM now, with the 800 miles on it. I wouldn't change the oil just to reset the monitor. Reset the monitor without changing the oil, then drive it a few hundred or thousand miles to see how the OLM reacts. Then you'd have a better idea of accuracy.

newdude · April 5, 2020

On 4/3/2020 at 6:10 AM, unit said:

I picked up my 2020 Silverado 2500HD with the Duramax engine on March 2nd. I have just over 800 miles on it and it's showing 40% oil life on the dash. If I bring up vehicle diagnostics on the My Chevrolet phone app, it will alternate between 89% and 40%. That is it may show 40% on the app when first checked and then show 89% if I update the app display. I know 40% is wrong and I'm planning on changing both oil and oil filter at 1K just so I can zero out the oil life monitor. The truck has a July 2019 build date and had 74 miles on it when I picked it up. Any ideas why this is happening? It's just kind of strange but will probably be OK after the oil is changed and the oil life is zeroed out the first time.

Truck was built in July 2019 but you just bought it March 2020? It went down due to the time it sat on the lot. Normal to have that happen. Just do a reset on it and it will be fine.

If the vehicle is hardly driven/not driven for a long period of time, the OLM will count the percentage down based on a 1 year timer. So if the truck was on the lot for 12 months from when it was delivered, it would have automatically zeroed out and said "change oil soon" on the dash. Chevrolet Volt owners are the most common folks to experience the OLM going to zero in a year if the engine never runs except in maintenance mode.

Edited April 5, 2020 by newdude

unit · April 5, 2020

Makes sense. None of my prior vehicles seemed to care about the age of the oil but I guess that's a factor. I do wonder though, why the app would show different percentages. I'll chalk that one up an an FM.

newdude · April 6, 2020

On 4/4/2020 at 10:47 PM, unit said:

Makes sense. None of my prior vehicles seemed to care about the age of the oil but I guess that's a factor. I do wonder though, why the app would show different percentages. I'll chalk that one up an an FM.

Not really based on the age of the oil. There is no "oil condition indicator" or any sort of sensor that actually determines the physical condition of the oil. The GM OLM primarily bases its countdown on RPMs, engine oil temperature, and other data. As of 2013, they did add mileage as a data set for the OLM with an internal cap at 7500 miles. If there is minimal driving of the vehicle/no driving at all (sitting on a lot/long term storage), then the OLM counts down by time until it reaches 1 year/365 days as well.

Edited April 6, 2020 by newdude