Real life experience with the oil life monitor system.

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I don't usually drive cars long enough to actually require an oil change, I usually just change it after purchase if the oil doesn't look too clean, or before I sell it if it looked good then.

Anyway, I've had this 07 Silverado 6.0 tow truck for years, and the CHANGE OIL message just came on. Checking my records for the last time I changed it, and it was 2 years and 11 months ago and it's gone about 2,800 miles. Doesn't that contradict most owners manual recommendations of changing the oil at least every year, regardless of the miles driven?
 
Here is what the OLM has indicated for our 07 6.2L Yukon Denali since we bought it 5+ yrs ago:
OLM data:
25% remaining after 8100 miles, 3 of 19
50% remaining after 6200 miles, 7 of 19
35% remaining after 7800 miles, 9 of 19
25% remaining after 8600 miles, 3 of 20
13% remaining after 10,200 miles, 3 of 21
31% remaining after 6750 miles, 4 of 22
??% remaining after 8600 miles, 12 of 22
39% remaining after 7600 miles, 9 of 23
51% remaining after 5100 miles, 3 of 24
 
It may contradict a lot of advice that you get everywhere, but that's not what the OLM is designed for.
GM olm is designed to keep your cost of ownership low, and the environment cleaner. The algorithm in the olm takes multiple factors into account and determines by math, the depletion rate of the oil additives.
If you really want to know if it worked in this case, take a sample and send it off to the lab of your choice.
 
I don't usually drive cars long enough to actually require an oil change, I usually just change it after purchase if the oil doesn't look too clean, or before I sell it if it looked good then.

Anyway, I've had this 07 Silverado 6.0 tow truck for years, and the CHANGE OIL message just came on. Checking my records for the last time I changed it, and it was 2 years and 11 months ago and it's gone about 2,800 miles. Doesn't that contradict most owners manual recommendations of changing the oil at least every year, regardless of the miles driven?
I guess it's up to the automaker as to whether they program the OLM to trip at the lesser of 1yr or X-miles. BMW for example didn't always program the lesser or 1 yr or X-miles in their OLM.
 
I had a 2006 Chevy with an OLM. It doesn't have a clock so it has no way of knowing if a year has gone by. When the car was at a dealer, the OLM was re-flashed to never exceed 7,500 miles. It might be at %60 remaining at 6,000 miles but it will count down quickly to zero by 7,500 miles. I like the OLM as it keeps track of short trips, cold temps etc. If you think it goes to far on an oil change, just change oil with %25 remaining or whatever you chose.
 
Honda requires an annual oil change but, in older versions at least, the oil life monitor doesn’t use time as a trigger.
 
GM didn't program and hard limits in the OLM until around 2011, when dexos first came out. For most cars, it became one year of 7500 miles max. The exception is the Volt, which is 2 years max, no mileage limit.

The limits were implemented after they started having problems with some of the HF V6 timing chains with DI. That's also when they developed dexos.

Older GM cars with the OLM have no limits programmed in, but the owner's manual said not to go more than 12k or a year.

On your truck, that's less than 1000 miles in a year. It probably is OK to only change it once every 3 years with such low use.
 
Doesn't that contradict most owners manual recommendations of changing the oil at least every year, regardless of the miles driven?
Before OLMs existed, the time-based requirements for OCIs were there to force an oil change at lower miles, since low miles over a long time might indicate that the vehicle is mostly short-tripped. An OLM allows the time requirement to be eliminated or greatly extended, since it knows how much the vehicle is short-tripped with a cold engine.

Some OLMs still have a time requirement, but this is probably just to get vehicles into the dealership more regularly for other services. Not sure if yours should have tripped sooner, but a 3-year 3k mile OCI is pretty reasonable if the engine spends most of its running time at operating temperature.
 
Here is what the OLM has indicated for our 07 6.2L Yukon Denali since we bought it 5+ yrs ago:
OLM data:
25% remaining after 8100 miles, 3 of 19
50% remaining after 6200 miles, 7 of 19
35% remaining after 7800 miles, 9 of 19
25% remaining after 8600 miles, 3 of 20
13% remaining after 10,200 miles, 3 of 21
31% remaining after 6750 miles, 4 of 22
??% remaining after 8600 miles, 12 of 22
39% remaining after 7600 miles, 9 of 23
51% remaining after 5100 miles, 3 of 24
The ones in Ford pick ups pick ups seem like count down meters.
 
The one on the Escape was definitely “intelligent” and would vary its recommendation based on a variety of factors. Although I did adjust its “base” to a longer OCI using Forscan. Super neat feature.

I think GMs have been “intelligent” for years. For sure the one in the Volt was smart. A trip from SF to LA and back in a day basically at the speed governor on a 100 degree day barely lost me a few % even though it was a lot of miles. It obviously knew that although I was basically loading the engine to full power for hours at a time it was easier on the oil than a bunch of stop-start cycles. While a few weeks of hybrid usage if I hadn’t been able to charge the battery would lose a %.

By now I think Honda’s were just timers/mileage counters for a long time but I think todays are intelligent.

Overall I think for the most part intelligent or adaptive or whatever you want to call them oil life monitors are a good thing. And you can achieve a reasonable lifespan out of the vehicle using them.

That said, there will always be cases where the OLM needs to be ignored and oil changed sooner. I don’t think the penalty in most of the systems for short tripped GDI engines is aggressive enough, for example.

The bigger problem is people don’t check their oil enough. I’ve never really had any oil burners except maybe my 01 Suburban with 300K that burned a quart every like 4K miles way back when but so many cars, even newer ones, do tend to use oil. And when you extend oil changes you have to check it. While if you change it every 3K miles you’ll probably never get low enough to need to add oil unless you have a serious problem.

For example, if it takes 6 quarts of oil and burns 0.5qt/1K miles… at 3K miles you’ll still have 4.5 quarts, which is probably fine. While by 6K miles you’d have only 3 quarts, which is bad.
 
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My son is driving my father in laws former work vehicle, a 2014 Chevy Equinox V6. It now has 270,000 miles on it. It goes off at 5,000 miles and has been fed a diet of dealer and various quick lube 5w30 synthetics. Drives wonderfully.
 
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I went as low as 18% 6100 miles on GM1.5t had the oil tested by BS, came back great TBN above 3 all wear numbers were low. And I did 3 test with different oils, I probably could go to 5-10% per BS recommendations.
 
2005 GMC Yukon Denali with oil changed at dealership...sat 3 months before being bought...driven 4028 miles in 8 months (almost to the day) showing 5% in OLM when I purchased...I changed oil 135 miles later to ACD filter and full synthetic 5W30...

after another 3605 miles and indicating 30% on the OLM after 6.5 months I had oil changed again (early) with full synthetic and Champ XL synthetic media filter...

after another 2.5 months and 1680 miles it is currently showing 63% on the OLM...I plan to wait until between 4-5K miles or single digits on the OLM...

I believe the OLM may have been updated when it had an oil change at a GM dealership last August and I use Dexos1 Gen3 full synthetic oil with a good filter despite the original spec being Dino oil in the 5W30 flavor...

Bill
 
On my 2007 G6 beater original owner the OLM is useless it kicks off for a oil change at 8k miles on conventional oil my opinion way to long. I now change twice a year ignore the OLM. On my newer GMs they kick off at about 4k calling for dexos approved so it's synthetic I follow the OLM. The early years GM OLM if followed led to engine disaster my opinion
 
I'm kind of impressed that the OLM is at 50% with about 3000 miles on the oil/filter on my 2021 Chevy Traverse.

It does seem to react more aggressively than other OLM equipped, non GM vehicles I've owned.

With the Traverse, I won't go beyond a 5K mile OCI anyway. It's a GDI 3.6L with a mile of timing chains, sprockets, guides, etc.. What could go wrong.
 
I change my 2014 Fusion 2.5L at 5000 miles (or a little more) and I do reset to 100% so it doesn't come on half way through. I believe it's usually around 50-60% when I reset it but it's just something Ive5 never relied on for my OCI.
On my part time job side, I work as a driver for Enterprise and our cars pop up for oil and filter changes at 7500 miles. Those miles are as reported by either the customer upon return or by the detailers when the cars are detailed.
I can only speak for my branch, at a smaller airport, that we do change the oil when that threshold is met and we disregard the OLM. As for other branches and other companies? I imagine there's plenty that just log an oil change and carry on.
 
Hondas is supposed to be intelligent, but I'm not so sure. 1800 miles on my FL5 and the monitor is at 90%. I have 1 mile short trips to the gym, on the highway the thing is spinning at 3600rpm, and I drive it hard in the twisties. I'll stick with changing at 3k+- so all it really does is remind me to check other maintenance things.
 
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