# OLM reads 24% at 2100 miles..??



## Sour Kruat's 951 (Nov 9, 2010)

I have 3200 and it is at 3%. Mostly city driving with no extended warm ups. 

It has been said it will last longer when driving hwy miles as opposed to city driving. The start stop intervals vs mileage are what cause the OLM % to drop fast.


----------



## yourdoinitwrong (Aug 7, 2011)

The calculation is based on an algorithm that takes into account the trip length, cold starts, idling, acceleration vs. steady crusing, and a bunch of other things that are way over my head. This is how it was explained to our dealership sales staff by the GM product trainers. With a lot of short trips it is very feasible that the reading is correct. My Cruze has 2,800 miles and my oil life is at 73% because I do a fair amount of highway driving.


----------



## CLUBGUY (May 28, 2011)

Considered safe to leave your first oil change to go below 10%....10% is when we plan to change....


----------



## bartonmd (Jun 30, 2011)

It's the short trips and not getting fully warmed up...

Mike


----------



## bartonmd (Jun 30, 2011)

yourdoinitwrong said:


> The calculation is based on an algorithm that takes into account the trip length, cold starts, idling, acceleration vs. steady crusing, and a bunch of other things that are way over my head. This is how it was explained to our dealership sales staff by the GM product trainers.


It does account for all of those things, but what it's really doing is counting engine revolutions, and weighting them based on engine temperature and engine load... 

Mike


----------



## yourdoinitwrong (Aug 7, 2011)

bartonmd said:


> It does account for all of those things, but what it's really doing is counting engine revolutions, and weighting them based on engine temperature and engine load...
> 
> Mike


I think that was that part that went over my head! :icon_scratch:


----------



## bartonmd (Jun 30, 2011)

yourdoinitwrong said:


> I think that was that part that went over my head! :icon_scratch:


e.g. it's just really guessing (and very well, at that) all of those other parameters by just looking at engine cycles, engine load, and temperature...

Mike


----------



## DanRS (Aug 23, 2011)

wow, I am at 5000 and my oil life is at 55%. Dont know if I trust it though, I may just get her serviced.


----------



## gman19 (Apr 5, 2011)

I did my first oil change at 2000 miles. I am currently at just over 4300 miles on the odometer (2300 miles since oil change) and my OLM is reading 77%. I do have a mostly (85% or so) highway drive to work. My daily commute is about 56 miles round trip. I'd gather that longer trips do extend oil life.


----------



## Crewz (Jul 12, 2011)

I live in Houston and the traffic to work is always bumper to bumper. It takes me 1 hour to travel 18.8 miles. It's been a hot summer (100º+) and I always let the car warm up. When it was time for my tire rotation at 6K miles, my oil life monitor stated I had 34%. I had the dealer change my oil while they rotated the tires. They told me, you still have 34% left and I didn't need a change. I told them to change it anyways.

Make of it what you will.


----------



## FatKidsCruze (Sep 2, 2011)

Mine is at 67% at 3400 miles, mostly city probably 70%.

Changed at 2600 and 75%, but did not reset OLM to see how far it will go.


----------



## RS LTZ (Jan 5, 2011)

50% at 5,400 miles. But I drive 80 miles hwy daily.


----------



## sedanman (Dec 10, 2010)

Crewz said:


> I live in Houston and the traffic to work is always bumper to bumper. It takes me 1 hour to travel 18.8 miles. It's been a hot summer (100º+) and I always let the car warm up. When it was time for my tire rotation at 6K miles, my oil life monitor stated I had 34%. I had the dealer change my oil while they rotated the tires. They told me, you still have 34% left and I didn't need a change. I told them to change it anyways.
> 
> Make of it what you will.


I changed my oil early too. But I don't want the dealer doing it. From what I hear they use a synthetic blend and even though it is dexos1 certified, i prefer Mobil1 full synthetic also Dexos1 certified.

On this car it's so much easier to change the oil and filter compared to my old car. It's actually enjoyable to do when the weather is nice out. Speaking of which I did it now when it's nice out, because soon winter is coming to my neck of the woods and I won't be doing it when it's freezing out.


----------



## got_boost (Sep 29, 2011)

CLUBGUY said:


> Considered safe to leave your first oil change to go below 10%....10% is when we plan to change....


....first new car?
First should be < 100 miles
Second < 1000 miles
Third < 2000
Then you can go off OLM
You have no idea how much shavings are left in the engine after it leaves the plant.


----------



## FatKidsCruze (Sep 2, 2011)

got_boost said:


> ....first new car?
> First should be < 100 miles
> Second < 1000 miles
> Third < 2000
> ...


Actually this is not as correct as it once was. Due to advances in technology and the materials used in today's engines plus the testing prior to installation, there is not much of a break in necessary maybe a few hundred miles.

When I changed mine at 2600 there were no metal shavings in the factory fill oil.


----------



## inspiruze (Jul 4, 2011)

Jesus, I'm at 3800 miles, and 62% left on my OLM. I changed out the FF at about 2k miles with QSUD 5W-30.


----------



## got_boost (Sep 29, 2011)

FatKidsCruze said:


> Actually this is not as correct as it once was. Due to advances in technology and the materials used in today's engines plus the testing prior to installation, there is not much of a break in necessary maybe a few hundred miles.
> 
> When I changed mine at 2600 there were no metal shavings in the factory fill oil.


 really? I had shavings in mine. Was't as much as I've seen in new engines before...but they were still there. My friends family owns a few Midas' here in Az and he said he changed oil in a new Camaro not too long ago and the amount of shavings astonished him.


----------



## Aeroscout977 (Nov 25, 2010)

got_boost said:


> really? I had shavings in mine. Was't as much as I've seen in new engines before...but they were still there. My friends family owns a few Midas' here in Az and he said he changed oil in a new Camaro not too long ago and the amount of shavings astonished him.


This. 

My g6 has the LY7 which was the precursor to the LLT DI V6 and on its first oil change had shavings. My Honda on the other hand had very little even in the way of a metallic sheen so I've seen both ends of the spectrum 



Edit: I don't even want to talk about how bad my Korean bike was.... 



Sent from my Autoguide iPhone app


----------



## RS LTZ (Jan 5, 2011)

The first change I believe should always been done around the 1000 mile mark. Every engine is built just slightly different and the amount of metal shavings therefore varies. To be on the safe side just change early. After the first the OLM is a great tool.


----------



## 70AARCUDA (Nov 14, 2010)

_"...You can never change the oil TOO *SOON*, only TOO *LATE*..."_


----------



## FatKidsCruze (Sep 2, 2011)

70AARCUDA said:


> _"...You can never change the oil TOO *SOON*, only TOO *LATE*..."_


Amen! Words of wisdom there!!!


----------



## got_boost (Sep 29, 2011)

RS LTZ said:


> The first change I believe should always been done around the 1000 mile mark. Every engine is built just slightly different and the amount of metal shavings therefore varies. To be on the safe side just change early. After the first the OLM is a great tool.


Word. I did mine at about 100 miles lol.


----------



## cruze01 (Mar 25, 2011)

Guys, check out the link below. Its the best explanation on the GM OLM system I've found yet.

ZDP depletion and GM oil life monitor - Bob Is The Oil Guy


----------



## yourdoinitwrong (Aug 7, 2011)

cruze01 said:


> Guys, check out the link below. Its the best explanation on the GM OLM system I've found yet.
> 
> ZDP depletion and GM oil life monitor - Bob Is The Oil Guy


Thanks, very interesting info.


----------



## cruze01 (Mar 25, 2011)

So, explain that to a dummy. Is it goog or bad? Do you trust the OLM?


----------



## cruze01 (Mar 25, 2011)

Interesting. Since this was formulated 10 years ago for a diesel engine I bet it has changed somewhat for a 4 cylinder gas engine today.


----------



## cruze01 (Mar 25, 2011)

I believe that the system probably works fairly accurately. Taking into account the items that the engineer on BITOG said about different wear points in different engines and the different grades of oil I'm sure they take all that into account and adjust the allowable engine revelations and adjust the other perimeters of the calculation. I don't know that I'm comfortable with a 10,000 mile oil change which is what my car wants to do but that doesn't mean its wrong, just that I'm brain washed to the 3000 mile rule.


----------



## curvedinfinity (Nov 23, 2011)

I did my Cruze's first oil change at 13,840 miles at 0% on the OLM.










Performed a Blackstone UOA on the oil, and Blackstone said the oil was still in great condition.










The next oil change based on my OLM is currently around 27500. At this rate I'll have done only 8 oil changes by the 100k mark. My car has the 1.8L motor and I drive 60% highway, 40% town. I'm amazed how care free this motor is. 

Follow the oil life monitor!


----------



## yourdoinitwrong (Aug 7, 2011)

curvedinfinity said:


> I did my Cruze's first oil change at 13,840 miles at 0% on the OLM.
> 
> Performed a Blackstone UOA on the oil, and Blackstone said the oil was still in great condition.
> 
> ...


That's pretty impressive. The only thing that looks out of line is the magnesium.


----------



## curvedinfinity (Nov 23, 2011)

yourdoinitwrong said:


> That's pretty impressive. The only thing that looks out of line is the magnesium.


Yeah, it was a pleasant surprise. I was a bit skeptical myself, but coming from doing HPDEs with a VW GTI with a 2.0T that had about every issue imaginable -- and service intervals of 10k, I figured "how much could go wrong on a simple, understressed motor like this?" It gets redlined at least once per day as well. The oil change process is about as easy as it gets too. -- A great car if I've ever seen one.


----------



## mr_raider (Aug 13, 2011)

curvedinfinity said:


> The next oil change based on my OLM is currently around 27500. At this rate I'll have done only 8 oil changes by the 100k mark. My car has the 1.8L motor and I drive 60% highway, 40% town. I'm amazed how care free this motor is.
> 
> Follow the oil life monitor!


Would the results be comparable for the 1.4T? I assume the oil in the turbo is subject to more abuse.


----------



## curvedinfinity (Nov 23, 2011)

mr_raider said:


> Would the results be comparable for the 1.4T? I assume the oil in the turbo is subject to more abuse.


Well, you never know. GM does the same validation testing on all its motors, so chances are it is pretty stout with its oil as well.


----------



## 70AARCUDA (Nov 14, 2010)

...each GM ENGINE application has its OWN operating OLM *profile* which includes the turbocharger 1.4LT LUJ engine.


----------

