Jeep grand cherokee oil life percentage

So, the dealership always put a windshield sticker on at each of the 4 "free" oil changes for 3000 miles. Am done with the 4 free ones and am now going to do it myself.

Am coming up on 3000 miles and looked at the oil life number and it is at 69%. Should I trust that, or stick with miles? I apologize if this is a "religious" discussion. I am new to vehicles that tell me when to change the oil and don't know what to think.

Mine was doing the same, but this time said it was 0% life left after 3,000 miles. So I figure they didn't reset the monitor. I do it every 5k miles regardless of what any monitor says to do.

I also change every 5k miles regardless of of the monitor.

Doing it on the fives is also very easy to keep track of.

My dealer does that too.. I'm at 12,000 miles and I've had them do two oil changes so far with full synthetic... Each time they put a sticker on the window showing the next oil change is 3000 miles. The first time, they didn't reset the mileage meter.. But, this last time they did. (Must have forgot to do it the first time).

This is a pure money grab and nothing else. The first thing I do is peel the sticker off and throw it away. I keep track of my mileage and go in at 5000 miles. Like many on this forum also do my own five tire rotation as well.

Every 5k miles here using pennzoil 5w20 synthetic. Sufficient buffer so if I miss by 2 or 3k or if I wheel, I should still be okay.

I go with the oil life monitor on the Jeep. Figure the engineers of the vehicle know more than I do and I change it when it gets to around 10% or less. Works out to about 9K miles. I have had no issues with my Jeep so far, in the 17 months and 33K miles put on it.

I suspect a lot of it is how the Jeep is used.

Here is an interesting perspective and test I have. I once asked my Chevy service about that very issue (now i do all of my own oil changes). Their response was that the vehicle's computer monitors how the vehicle was driven and calculates the % of oil life left "assuming synthetic specs used". I really didnt pay too much attention to it as I am avid believer of "clean oil is the best oil" and i always use Mobil 1 pure synthetic and either K&N or M1 filters. However, I do all my vehicles at 5,000 or 1 year.

After reading LOTS of oil threads lately, I decided to test this computer related oil life reading. Granted this was in 2 Chevrolet vehicles but I suspect all vehicles are similar.

We were about to go on a family trip that required us taking my wife's suburban (2012 w/ 136,000 miles) and my Silverado 1500 truck (2011 w/ 126,000 miles). Both vehicles have the same motor and transmission. Heck they even both take the same oil specs, quantity, and filters. The only difference is the suburban was loaded with people and such while the truck was towing a trailer with my jeep on it and some other items and the bed was loaded. Truck in tow mode too. I changed BOTH vehicles oil and reset the oil life setting the day before we left. After 600 miles round trip, the suburban sat at 92% while my truck was at 74%.

So, IMO and crude testing, it does appear that the onboard computer does do some sort of drive style monitoring and adjusts accordingly. Truck was using higher RPMs throughout the trip at same speeds.

I will still stick with my 5,000 mile rule though.

My guess on the possible inputs involved in the remaining oil life calculation:

Coolant/block temperature
Oil pressure
EGT
MAF (Mass air (and fuel) flow, which could translate to load %)
RPM
RPM change over time

These parameters, and interactions of them likely comprise the algorithm GM, Chrysler, and many others use to predict when an oil change is necessary. Very likely, the weight and additional loads on a vehicle during normal driving will easily be shown in these measurements. These predictive equations may be accurate to within a few hundred miles by now. I certainly don't fault the 5000 miles rule for ease of keeping track however.

I believe that the computer does an accurate job, but I change mine at 5k miles regardless.

Interesting video:

Two of my vehicles (Jeep included) have oil life monitors. That's what I go by, unless the Jeep was driven under severe conditions. Then I change the oil every 4000 miles, per the owner's manual. My other two vehicles don't have OLMs, so I change according to the maintenance schedule in the owner's manual. I use Mobil 1 in all of them.

All I will say about the "oil life monitoring system" is; I have about 72,000 miles on my '15 JKU.... anybody wanna guess how many times it has called for an oil change? 3 times in 3 years/72k miles - IMO that is ridiculous.

(Oh God! I just posted in an oil thread.....Run!!!)

My guess on the possible inputs involved in the remaining oil life calculation:

Coolant/block temperature
Oil pressure
EGT
MAF (Mass air (and fuel) flow, which could translate to load %)
RPM
RPM change over time

These parameters, and interactions of them likely comprise the algorithm GM, Chrysler, and many others use to predict when an oil change is necessary. Very likely, the weight and additional loads on a vehicle during normal driving will easily be shown in these measurements. These predictive equations may be accurate to within a few hundred miles by now. I certainly don't fault the 5000 miles rule for ease of keeping track however.

Except FCA uses MAP sensors, not MAF sensors.

I keep track of my miles and shoot for 7500 with full synthetic. So far the onboard computer seems to alert at around 7500. I wouldn’t change at any less than 5000. There are plenty of articles and oil analysis on multiple vehicles that have all proved oil works for well over 5k under normal driving. I wouldn’t be surprised if your good to 10k. I do a lot of highway driving so I’m even less concerned about oil life.

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I will not post in another oil thread.
I will not post in another oil thread.
I will not post in another oil thread.
I will not post in another oil thread.
I will not post in another oil thread.

(Every 5K with a 5-tire rotation)

I will not post in another oil thread.
I will not post in another oil thread.
I will not post in another oil thread.
I will not post in another oil thread.
I will not post in another oil thread.

All I will say about the "oil life monitoring system" is; I have about 72,000 miles on my '15 JKU.... anybody wanna guess how many times it has called for an oil change? 3 times in 3 years/72k miles - IMO that is ridiculous.

(Oh God! I just posted in an oil thread.....Run!!!)
View attachment 4084539

That hot dog is about to get rapedddd.

Tell Ya what..... IF that chick ran in my room in the middle of the night and grabbed hold of my 6 sp MT - I'd (probably) let her go to town - at least until my Wife woke up and kicked her ass.

Wifey is picky about who shifts my gears ..... I'm good with that.:drinks:

I mostly change oil on all our vehicles at some point between 3k-5K. If the monitor comes on it is changed at that point other wise between 3-5K depending on several things.
Towing (3K) vs all highway and no load I will go to 5K. Also if we are going on a long trip or something I may change it before the 5K mark to make sure it is clean and ready to roll. Even if I had to do 10 a year I have what, maybe $400 in it? That is cheap insurance, and after well over 1 million miles on our cars we have never had a oil related problem or issue so I am thinking my system works for us.

All I will say about the "oil life monitoring system" is; I have about 72,000 miles on my '15 JKU.... anybody wanna guess how many times it has called for an oil change? 3 times in 3 years/72k miles - IMO that is ridiculous.

(Oh God! I just posted in an oil thread.....Run!!!)
View attachment 4084539

There must be something wrong with yours. Mine gives me lets me know to change mine much more often than that. But that is why the owner's manual also has a one year, 10,000 mile oil change interval if the oil life monitor doesn't give you an indication first.

I go with the oil life monitor on the Jeep. Figure the engineers of the vehicle know more than I do and I change it when it gets to around 10% or less. Works out to about 9K miles. I have had no issues with my Jeep so far, in the 17 months and 33K miles put on it.

I suspect a lot of it is how the Jeep is used.

It's your Jeep and I'm not saying that your motor is going to blow up, but my owners manual ('16) states not to exceed 8K miles no matter what the monitor states.

It's your Jeep and I'm not saying that your motor is going to blow up, but my owners manual ('16) states not to exceed 8K miles no matter what the monitor states.

From pg. 611 of the 2016 Wrangler owner's manual:

NOTE: Under no circumstances should oil change intervals
exceed 10,000 miles (16,000 km), twelve months or
350 hours of engine run time, whichever comes first. The
350 hours of engine run or idle time is generally only a
concern for fleet customers.