LM2 Duramax Oil Analysis - Blackstone Labs Report

[StephenPT]

I've not seen many engine oil analysis reports on our faithful LM2 motors, so I thought I'd share the one I got back just today on my '22 Yukon XL.

I did my first oil change at ~1,300 miles. Second was at ~5,300 so ~4K miles on the oil change that is shown in this report. Overall good numbers - I appreciate the personal response they give you as it helps to explain some of the info. I also paid extra to get a TBN value, which essentially shows how much life is left in the oil. At 4.9 TBN and the bottom threshold being 1.0, I'll probably extend my next oil change to ~6K miles. I don't plan to pay for one of these oil analysis reports every time I do it, but might do another one when we're at ~30K or so on the clock.

 

[Stbentoak]

It pretty much reinforces that these vehicles can easily go 7500 miles plus on any approved DexosD oil. I would have zero qualms about running the 7500 limits if needed, but I basically change it when time and nicer weather situations arise.
Most oils today can actually go further than most people think, but it still doesn't change their minds...
For the cost of it, I always at least try to get my full mileage out of it....

 

[Fireman591]

It pretty much reinforces that these vehicles can easily go 7500 miles plus on any approved DexosD oil. I would have zero qualms about running the 7500 limits if needed, but I basically change it when time and nicer weather situations arise.
Most oils today can actually go further than most people think, but it still doesn't change their minds...
For the cost of it, I always at least try to get my full mileage out of it....

I agree. I change mine around 7500-8000 miles and replace my filter every 4000 miles. I use the Purolator PureOne filters. The oil can last a long time but you don't want a dirty filter to start bypassing. For 8 bucks it is worth the added insurance.

 

[Stbentoak]

How do you change your filter without draining the oil? From my experience, the oil level is up over the filter port when full. Don't you get an oil bath?
I use the AC Delco gold filter. I believe it's the better balance of price to build quality/longevity. You can tell it is not a cheap filter, by its components and heft compared to a say PF66. I believe this filter could go 15K no problem.

 

[ChasingRedline]

Check out Baldwin Filters. All I use now.

 

[Scott in AZ]

Wait …. What? You change your filter X4000 miles and leave the oil in ?

 

[swathdiver]

Wait …. What? You change your filter X4000 miles and leave the oil in ?

And there are people who change the oil every 4K miles and the filter every 8K miles!

I do a sample every year on the motor. You can see the difference in metals after we did away with Mobil One for ACDelco oil.

 

[Stbentoak]

And there are people who change the oil every 4K miles and the filter every 8K miles!

I do a sample every year on the motor. You can see the difference in metals after we did away with Mobil One for ACDelco oil.

Sometimes there are mitigating circumstances that might make this necessary. I can change my oil in less than 15 minutes with a valve and a container with zero mess. There is about a half a quart of old oil in the filter. 6 1/2 quarts of new oil. Nothing wrong with that in my mind as long as you are using quality filters. Better to do this than do nothing. Quality filters can do 15k....