olm

[wadedog]

In my 2005 silverado 4x4, does the olm adjust for syn oil ?
I put in mobil 1 syn about 3000 miles ago and now my olm is asking for oil change.

Is there any way it can tell me how much life is left in my oil before it asks for a change?

Can i trust the olm to KNOW if the oil is still good or is this just a gadget made by gm to support 3000 mile changes.

 

[jorton]

I've been wondering how the OLM works? Do you manually reset it when you change the oil?

 

[BR549]

http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=1;t=010523

 

[Schmoe]

Yeah, I find that really hard to believe your OLM is asking for a change at that low mileage.

 

[302Xplorer]

quote:

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Originally posted by wadedog:
In my 2005 silverado 4x4, does the olm adjust for syn oil ?
I put in mobil 1 syn about 3000 miles ago and now my olm is asking for oil change.

Is there any way it can tell me how much life is left in my oil before it asks for a change?

Can i trust the olm to KNOW if the oil is still good or is this just a gadget made by gm to support 3000 mile changes.

---

Did you reset your olm after you changed your oil?

 

[farrarfan1]

Wadedog on my wifes 05 Uplander you can toggle through the information center to see what the remaining oil life is.From the information posted by the GM engineer the OLM does not differentiate between synthetic or conventional. It is calibrated using conventional and is very conservative. There have been a few UOA's posted that seem to verify it works pretty accurately. My guess is that either you do a lot of short trip driving in cold weather or you forgot to reset it when the oil was changed.That would account for it showing oil change at 3K.

 

[mjpolge]

The olm does not adjust for synthetic oil. It calculates the oil life based on a lot of factors such as engine rpm, trip length, engine temperature, etc. I have an olm on my '04 Trailblazer and it runs about 7k before it asks for an oil change.

 

[Matt_S]

The Silverado doesn't appear to have a way to show the percentage of oil life remaining. It can be seen with the right scan tool, though. To reset it, turn the ignition on without starting the engine and press the gas pedal three times within 5 seconds. You should see a message indicating the system is resetting and the "Change Engine Oil" message should not appear the next time you start the engine. The reset needs to be done every time you change the oil. Personally, I've never seen one come on in less than 5k miles. It was designed to allow people to safely extend their OCIs. I believe this was developed under pressure from the government to come up with a way to reduce oil usage.

To answer jmacmaster's question, I would expect those parameters to be factored into the equations the computer uses to monitor the oil life. There's no way the computer can monitor the actual condition of the oil in terms of oxidation, fuel dilution, particle counts, PPM levels of various elements, etc. The only variables that can really be monitored are run time, engine revs, temperature, etc.

 

[wadedog]

I reset the olm after the oil change.
I just changed over today to PP from mobil 1 and no more noise from the valve train, woo hoo.

I'm paying alot more attention now to this oil and i'll see how long this batch lasts.
I do alot of short trips.
thanks for all the info.

 

[Matt_S]

quote:

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Originally posted by wadedog:
I do alot of short trips.

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That's why it only allowed you 3k. You get penalized for engine operation below or above normal operating temperature. Idling will also penalize you. A lot of short trips means more time than normal below operating temperature and usually more idling time. This equals a shorter OCI according to the computer.

 

[jmacmaster]

I just read the excellent 5 page thread that BR549 cited us to. One thing is not clear to me. Does the OLM monitor for, detect, measure, and take into account pollutants that enter the oil, such as gasoline, engine coolant, and particulates that get past the air filter? From what I can tell, it doesn't.

 

[wadedog]

How long does a person need to drive to get longer oci's and to heat up all moisture etc. for better oil usage, any ideas?

 

[Matt_S]

My commute is 22 miles each way in typically heavy traffic (lots of stop-and-go). That's all the car ever gets used for these days. My OLM gives me about 6k per change. What would say the average length of your trip would be? Knowing the GM OLM, I'd say any time spent at operating temperature (the computer uses coolant temp, not oil temp, BTW) and moving will contribute toward a longer OCI. Warmup time and engine idling are the biggest factors in a short OCI.

 

[wadedog]

Well that probably explains things.
My daily commutes are about half or less some days that yours Matt.
Maybe i should switch to a decent dino oil instead of 6 dollar syn oil, if it's only going to last around 3k anyway.
What does everyone think ? should I ?

 

[Ken2]

When the OLM says to change the oil, don't...send a sample for analysis and reset the OLM. If the oil is OK, run until it says to change again. Change this oil and send that sample in. If the oil is not OK, run a good quality dino oil.


Ken

 

[Bill in Utah]

quote:

---

Originally posted by wadedog:
Well that probably explains things.
My daily commutes are about half or less some days that yours Matt.
Maybe i should switch to a decent dino oil instead of 6 dollar syn oil, if it's only going to last around 3k anyway.
What does everyone think ? should I ?

---

My 2000 Silverado 4x4 ext cab V8 gets short trips alot and the UOAs I did at 4k miles with Mobil 1 and Pennzoil Dino showed the Pennzoil having a better UOA then the Mobil 1 for the same OCI. At that time, I was driving the truck on longer trips, now it gets more short trips.

Because of this, I want to get the oil out of there since it's not getting up to temp EVERY trip.

I've never had my OLM go off under 5k miles but I heard that in 2002 the OLM had been repogrammed due to the better performance of SL oils.

I'd go with the OLM and a good Conventional oil.

You can't run syn long enough to make up the cost difference.

We have had some Chevy trucks go 12k miles using the OLM and their UOAs using dino have been pretty good.

I would not go that far. Esp in warrenty. (You'd be covered, but since the oil is cheap (ie even at todays prices, 6 qts will cost no more than $12)

I'd say 7500 miles would be the most I'd go and with short trips, 5k.

I'd just follow the OLM with whatever name brand oil is on sale since yours is going off before 5k.

Take care, Bill