What About An Oil Change?

[flyboyron]

I have 3,100 miles on the truck now and I was wondering if I should change the oil.

 

Doesn't the breaking in of the engine cause the oil to get dirtier sooner?

 

Just wondering if I change the oil if I would help clean out any break in debris.

 

I am showing 64% life remaining.

[usmc3529]

Yes change the oil.

 

That stupid oil life garbage is worthless, its just an "hourmeter" and is counting time anytime the vehicle is running. It does not tell you if your oil is dirty or breaking down

[RaddHazzard]

I would change it. Then on your next fill go with the OLM. I changed mine at 2500 the first time.

[chakis24]

yeah, change. why not? was does gm recommend?

 

Yes change the oil.

 

That stupid oil life garbage is worthless, its just an "hourmeter" and is counting time anytime the vehicle is running. It does not tell you if your oil is dirty or breaking down

 

false.

 

http://www.gm-trucks.com/forums/index.php?...8395&hl=olm

read post #5.

[RyanbabZ71]

wow I changed mine at like 550 miles. I am at 3100 now and I am changing again at 3500

[700 sportsman]

It wouldn't hurt to change it, and is you wanted to switch to synthetic, now would be a good time to do that

[dlstewart01]

Yes change the oil.

 

That stupid oil life garbage is worthless, its just an "hourmeter" and is counting time anytime the vehicle is running. It does not tell you if your oil is dirty or breaking down

 

This guy worked with Dr Shirley Schwatz who developed the algorythem GM used for the OLM.

 

http://hall.michiganwomenshalloffame.org/h...~95~216~166~187

 

The OLM does NOT just monitor engine revolutions. Each specific engine has a stored maximum "bank" of set engine duty cycles (revolutions) between OCIs, reset by the user at time of service. Each time the PCM fires, it subtracts the number of revolutions from the bank. When the bank = 0, the "Change Engine Oil" or oil light illuminates. Outside air temp, coolant temp, cold soak time, throttle load, vehicle speed, etc. are all accounted for in an effort to predict oil temperature, which in turn assess an exponential penalty factor. If the oil temp is above or below the standard algorithm allowance, the amount of degradation increases and is subtracted from the bank value at a higher rate. Hence, if you drive short trips in cold temps, the OLM ticks away faster. If you track your Vette with high rpm/loads, the OLM ticks away faster. If you tow, well you get the idea...

 

The ONLY thing the OLM cannot account for is a mechanical engine fault. If you have a leaky air filter or a coolant leak, the OLM will never know or change it's signaled OCI. This is where and oil condition monitor would be superior. GM chose this route for simplicity/cost. They are willing to stake a 5yr/100K powertrain warranty on it, so it can't be too terrible.

 

IMHO, the intervals are a bit on the high side, usually signaling for a change right at the time the oil is spent. I prefer a buffer of 10-20%, but have no qualms about going to 0%. I have yet to see a bad UOA by following the OLM

[AThomas7782]

Yes change the oil.

 

That stupid oil life garbage is worthless, its just an "hourmeter" and is counting time anytime the vehicle is running. It does not tell you if your oil is dirty or breaking down

 

This guy worked with Dr Shirley Schwatz who developed the algorythem GM used for the OLM.

 

http://hall.michiganwomenshalloffame.org/h...~95~216~166~187

 

The OLM does NOT just monitor engine revolutions. Each specific engine has a stored maximum "bank" of set engine duty cycles (revolutions) between OCIs, reset by the user at time of service. Each time the PCM fires, it subtracts the number of revolutions from the bank. When the bank = 0, the "Change Engine Oil" or oil light illuminates. Outside air temp, coolant temp, cold soak time, throttle load, vehicle speed, etc. are all accounted for in an effort to predict oil temperature, which in turn assess an exponential penalty factor. If the oil temp is above or below the standard algorithm allowance, the amount of degradation increases and is subtracted from the bank value at a higher rate. Hence, if you drive short trips in cold temps, the OLM ticks away faster. If you track your Vette with high rpm/loads, the OLM ticks away faster. If you tow, well you get the idea...

 

The ONLY thing the OLM cannot account for is a mechanical engine fault. If you have a leaky air filter or a coolant leak, the OLM will never know or change it's signaled OCI. This is where and oil condition monitor would be superior. GM chose this route for simplicity/cost. They are willing to stake a 5yr/100K powertrain warranty on it, so it can't be too terrible.

 

IMHO, the intervals are a bit on the high side, usually signaling for a change right at the time the oil is spent. I prefer a buffer of 10-20%, but have no qualms about going to 0%. I have yet to see a bad UOA by following the OLM

 

 

I wholeheartedly agree. As cheap as GM is getting about warranty work these days, why would they stake a 5 yr/100k warranty on a system like the OLM. Sadly, I think many of the dealerships do very little to help its viability by sticking oil change stickers on your windshield for every 3000 miles.

 

Not that I think someone is dumb for changing their oil to be extra careful, but it still doesn't make the system less viable.

[RaddHazzard]

yeah ive heard the OLM is pretty darn good. And if youre using synth oil you got all kinds of protection. I have always been a 3k mile oil changer, but im adding a few hundred miles to each one. I am gonna single handedly save the planet by going 7k miles on oil changes.

[usmc3529]

lol you guys will believe anything. The simple versaion of the above posts is a glorified hour meter, nothing more. I am a ford mechanic and they have the same thing. They try to say the same thing, but as we were taught in school by ford engineers and master techs is that it is just a glorified hour meter

[big_dawg74]

...as we were taught in school by ford engineers and master techs is that it is just a glorified hour meter

 

'nuff said...

 

 

Makes me happy I own stock in ExxonMobil.

[AThomas7782]

lol you guys will believe anything. The simple versaion of the above posts is a glorified hour meter, nothing more. I am a ford mechanic and they have the same thing. They try to say the same thing, but as we were taught in school by ford engineers and master techs is that it is just a glorified hour meter

Do you not think Ford engineers and Master techs are going to trash GM in any way possible?

[dlstewart01]

Tell the Ferd guys to figure out GM algorithm calculations.....And what Ford does has absolutely no bearing on GM engineering....

 

 

 

1. In a motor vehicle having a direct or an indirect injection diesel engine containing lubricating oil which has a useful life that varies in accordance with engine operating conditions, a method for advising the operator of the vehicle of the need to change oil, such method comprising the steps of:

 

Periodically calculating an effective engine revolutions value over predetermined intervals during a present engine operation in accordance with a product of measured engine revolutions and engine oil temperature and engine oil contaminant penalty factors which operate to increase the effective engine revolutions value to compensate for engine operating conditions that tend to cause increased degradation of the engine oil, the oil temperature and oil contaminant penalty factors being determined as a function of engine oil temperature and engine oil contaminant values, respectively;

 

Decreasing a stored remaining allowed revolutions value indicative of the remaining number of engine revolutions allowed for the useful life of the engine oil by subtracting the calculated effective engine revolutions value; and

 

Actuating an indicator advising the operator that the engine oil needs to be changed when the stored remaining allowed revolutions value falls below a predetermined threshold value indicative of the end of the useful life of the engine oil.

 

2. A method as in claim 1 further comprising the step of calculating the engine oil temperature value in accordance with engine parameters prior to calculating the effective engine revolutions value.

 

3. A method as in claim 1 further comprising the step of determining the engine oil temperature value by measuring an engine oil temperature from an engine oil temperature sensor prior to calculating the effective engine revolutions value.

 

4. A method as in claim 1 further comprising the step of calculating the engine oil contaminant value in accordance with an oil temperature value, fuel injection timing, fuel quantity and engine rotational speed prior to calculating the effective engine revolutions value.

 

5. A method as in claim 2 wherein the step of calculating the engine oil temperature value includes the steps of:

 

 

 

When the engine oil temperature value is in a warm up range, calculating the oil temperature in accordance with a measured initial coolant temperature at the beginning of a current engine operation and a sum of engine revolutions since the beginning of the current engine operation; and

 

When the engine oil temperature value is in an equilibrium range, calculating the oil temperature in accordance with a measured coolant temperature, engine rotational speed, fuel quantity, intake air temperature and vehicle speed.

 

6. A method as in claim 2 wherein the step of calculating the engine oil temperature value includes the steps of:

 

When the engine oil temperature value is in a warm up range, calculating the oil temperature in accordance with a warm up equation T.sub.o =T.sub.ic +k.sub.1 R.sub.e wherein T.sub.ic is an initial coolant temperature at the beginning of a current engine operation, R.sub.e is sum of the engine revolutions since the beginning of the current engine operation and k.sub.1 is a constant; and

 

When the engine oil temperature value is within an equilibrium range, calculating the oil temperature in accordance with an equilibrium equation T.sub.o =k.sub.2 +k.sub.3 S.sub.e +k.sub.4 T.sub.c +k.sub.5 F.sub.q -k.sub.6 T.sub.a.+-.k.sub.7 V.sub.s wherein S.sub.e is engine rotational speed, T.sub.c is a coolant temperature, F.sub.q is fuel quantity, T.sub.a is an air intake temperature, V.sub.s is vehicle speed, and k.sub.2, k.sub.3, k.sub.4, k.sub.5, k.sub.6 and k.sub.7 are constants.

 

7. A method as in claim 4 wherein the step of calculating the engine oil contaminant value includes the steps of:

 

calculating the engine oil contaminant value, C, from an equation

C=k.sub.8 +k.sub.9 I.sub.t +k.sub.10 F.sub.q +k.sub.11 T.sub.o +T.sub.o +k.sub.12 S.sub.e,

wherein I.sub.t is fuel injection timing, F.sub.q is fuel quantity, T.sub.o is the calculated oil temperature value, S.sub.e is engine rotational speed, and k.sub.8, k.sub.9, k.sub.10, k.sub.11 and k.sub.12 are constants.

[hockeypro1411]

lol you guys will believe anything. The simple versaion of the above posts is a glorified hour meter, nothing more. I am a ford mechanic and they have the same thing. They try to say the same thing, but as we were taught in school by ford engineers and master techs is that it is just a glorified hour meter

 

 

 

Tell the Ferd guys to figure out GM algorithm calculations.....And what Ford does has absolutely no bearing on GM engineering....

 

 

 

1. In a motor vehicle having a direct or an indirect injection diesel engine containing lubricating oil which has a useful life that varies in accordance with engine operating conditions, a method for advising the operator of the vehicle of the need to change oil, such method comprising the steps of:

 

Periodically calculating an effective engine revolutions value over predetermined intervals during a present engine operation in accordance with a product of measured engine revolutions and engine oil temperature and engine oil contaminant penalty factors which operate to increase the effective engine revolutions value to compensate for engine operating conditions that tend to cause increased degradation of the engine oil, the oil temperature and oil contaminant penalty factors being determined as a function of engine oil temperature and engine oil contaminant values, respectively;

 

Decreasing a stored remaining allowed revolutions value indicative of the remaining number of engine revolutions allowed for the useful life of the engine oil by subtracting the calculated effective engine revolutions value; and

 

Actuating an indicator advising the operator that the engine oil needs to be changed when the stored remaining allowed revolutions value falls below a predetermined threshold value indicative of the end of the useful life of the engine oil.

 

2. A method as in claim 1 further comprising the step of calculating the engine oil temperature value in accordance with engine parameters prior to calculating the effective engine revolutions value.

 

3. A method as in claim 1 further comprising the step of determining the engine oil temperature value by measuring an engine oil temperature from an engine oil temperature sensor prior to calculating the effective engine revolutions value.

 

4. A method as in claim 1 further comprising the step of calculating the engine oil contaminant value in accordance with an oil temperature value, fuel injection timing, fuel quantity and engine rotational speed prior to calculating the effective engine revolutions value.

 

5. A method as in claim 2 wherein the step of calculating the engine oil temperature value includes the steps of:

 

 

 

When the engine oil temperature value is in a warm up range, calculating the oil temperature in accordance with a measured initial coolant temperature at the beginning of a current engine operation and a sum of engine revolutions since the beginning of the current engine operation; and

 

When the engine oil temperature value is in an equilibrium range, calculating the oil temperature in accordance with a measured coolant temperature, engine rotational speed, fuel quantity, intake air temperature and vehicle speed.

 

6. A method as in claim 2 wherein the step of calculating the engine oil temperature value includes the steps of:

 

When the engine oil temperature value is in a warm up range, calculating the oil temperature in accordance with a warm up equation T.sub.o =T.sub.ic +k.sub.1 R.sub.e wherein T.sub.ic is an initial coolant temperature at the beginning of a current engine operation, R.sub.e is sum of the engine revolutions since the beginning of the current engine operation and k.sub.1 is a constant; and

 

When the engine oil temperature value is within an equilibrium range, calculating the oil temperature in accordance with an equilibrium equation T.sub.o =k.sub.2 +k.sub.3 S.sub.e +k.sub.4 T.sub.c +k.sub.5 F.sub.q -k.sub.6 T.sub.a.+-.k.sub.7 V.sub.s wherein S.sub.e is engine rotational speed, T.sub.c is a coolant temperature, F.sub.q is fuel quantity, T.sub.a is an air intake temperature, V.sub.s is vehicle speed, and k.sub.2, k.sub.3, k.sub.4, k.sub.5, k.sub.6 and k.sub.7 are constants.

 

7. A method as in claim 4 wherein the step of calculating the engine oil contaminant value includes the steps of:

 

calculating the engine oil contaminant value, C, from an equation

C=k.sub.8 +k.sub.9 I.sub.t +k.sub.10 F.sub.q +k.sub.11 T.sub.o +T.sub.o +k.sub.12 S.sub.e,

wherein I.sub.t is fuel injection timing, F.sub.q is fuel quantity, T.sub.o is the calculated oil temperature value, S.sub.e is engine rotational speed, and k.sub.8, k.sub.9, k.sub.10, k.sub.11 and k.sub.12 are constants.

 

I'm not trying to tell you how to do your job or anything, buuuut... yea. Take notes.

[brainpause]

I will soon be getting an oil analysis on near 0% OLM. Miles will probably be 6-7K. I'll try to add it to this or another topic.

 

Larry