I just looked at my oil life on the DIC and it says I have 15% left which will be at 5000 miles .

My LLY would go to 10k miles before the oil life was 0% !

Since the capacity is the same............I don't get it. Why would they drop it in half on the LMM ???

it calculates it by gallons of fuel burnt,duration of trips,and temp

Been towing heavy?

Those are usually quite off. Even running a good dino oil, I would run it to 10k plus if you are operating under average conditions, a good syn oil will go 10k+ without a problem. I run the Amsoil to 15k with no UOA.

Pull a sample of the oil and see what is going on. GM is experiencing some issues with short oil life. The oil life monitor has been accurate on mine with both 6K and 10K changes as it calls for. Oil samples back up that it is accurate.

Long regens like running around town while it is attempting a regen will eat oil life quickly. 650 miles took out 30% oil life for me one time.

Pull a sample of the oil and see what is going on. GM is experiencing some issues with short oil life. The oil life monitor has been accurate on mine with both 6K and 10K changes as it calls for. Oil samples back up that it is accurate.

Long regens like running around town while it is attempting a regen will eat oil life quickly. 650 miles took out 30% oil life for me one time.

Huge factor in the LMM oil life.

I had 5200 miles on my oil and the DIC read 45%. It just changes like others said on towing/load/city driving/regen etc. Do a oil sample and really know whats going on.

I just did an oil sample at 12,000 and the amount of fuel in the oil was pretty high according to the report, 5.4%

My DIC still said I had 10% left when I did the change.

As for running around town during the regen, I don't notice that as an issue, still seems to take the same amount of time and the same amount of fuel.

But as others have said, if you are not comfortable with that then have an analysis done.

Oil is cheap, engines are expensive.

Change it.

My oil life minder came on @10K, thats when I change it. Never had it come on early like some of you, but my truck is always on the highway...very little in town driving, that's what the VW TDI is for;)

amsoil has stated that there is fuel getting in the oil with the injectors squirting fuel on the axhuast stroke. But they say it is not enough to worry about. Maybe it is good to know with an analises what is going on. I think with 12000K and 5.4% fuel in the oil is a lot :eek: Not so sure I would want that much in there. They could be making the percentage drop faster on the Lmm vrs the lly because of just that fuel in the oil because of regen

Thanks guys !

New truck.......4200 miles. Mostly city driving , rarely tow. I have towed my boat 3 times this summer and it's only about 6500lbs !

So you guys think it's the re-gen with so many city miles ??? If so , this dpf may be coming off way before the warranty is up !

Blackstone Labs told me that they see slightly higher fuel presence in oil samples from the LMM. This is no doubt due to the regeneration process, which injects fuel at odd parts of the engine cycle.

That having been said, I trust the oil monitoring system completely. It is a patented system that has been tested over millions of miles and it works. An oil sample sent to a lab, as indicated by other members, proves that it works.

In my case, the oil life monitor has indicated at least 12,000 miles between changes, and the lab results from oil samples show that there was still life left in the oil.

The argument that oil is cheaper than an engine is not a logical argument because it is not supported scientifically. Even if there was some scientific proof that changing oil more frequently was beneficial, how long do you need your engine to last? I've always traded my truck before 300,000, for reasons other than the engine, so I don't care whether the engine lasts 400,000 or 427,324 miles. I'm therefore not interested in wasting money on unecessary oil changes.

Oil is cheap, engines are expensive.

Change it.

Why waste good oil? Over 100K on mostly 10K oil changes. And yes it was rear ended once. So I could have wasted a bunch of cash and had the truck totaled or stolen before I ever got any benefit from excessive oil changes. Oh wait there isn't any benefit to excessive oil changes except cost. Any problems like coolant or fuel in the oil will ruin the engine anyway unless you catch it first with a oil sample program.

I would be at the dealer with 5.4% fuel in the oil! I have never seen even 1% in mine. Except with biodiesel and the lab did not detect the B99.

Took it in today !! There is a TSB but no fix as of yet ...............they told me all I could do is change the oil and monitor the next cycle ! Wonder what the deal is ???????

Took it in today !! There is a TSB but no fix as of yet ...............they told me all I could do is change the oil and monitor the next cycle ! Wonder what the deal is ???????


CBM, there is a TSB for the oil life monitor or the frequent regens on your truck ?

Just curious as my dealer went out of business so, Now I have to fend for myself and most of my data comes from the fellow truck owners of the different forums.

Yeh. I will try to dig it out and give you the TSB #

It really does have to do with starting and going short distances. I took a 5000 mile trip this summer and towed by TT. My oil life went down about 50%. I changed my oil about 6 weeks ago and have driven probably less than 500 miles and the oil has dropped to about the same amount. This has to be because I have been driving about 8 miles a day and with short trips it really does make the oil life go down signifacantly. If this is how all engines operate, this is someting good to know if you don't have a monitor on your vehicle.