I used to change the oil every 5,000 miles. In 2023 I bought a new vehicle and stumbled onto the truck's on-board oil life monitor. At 5,000 miles it still has ~60% oil life.

It's also the first vehicle that I've used synthetic oil (except for my motorcycles).

Now it says my oil has 40% oil life left. How accurate are those things? Note: 99% of my driving is in town. Mostly on expressways.

Here's some background on what they measure, and what they don't: https://blog.amsoil.com/oil-li...ng-you-need-to-know/
They are estimates based on what they get as input from your vehicle's usage history, not actual measurements of oil viscosity/cleanliness/chemistry.

quote:

Oil life monitors track climate, driving habits and other conditions.

The algorithm calculates mileage, idle time, engine temperatures, trip times, engine loads, and ignition starts and stops.

It then establishes an oil change interval as low as 3,000 miles (4,800 km) and all the way up to 10,000 miles (16,000 km) and more depending on severity of conditions.

With the complexity of many of the late model engines and the high cost of repairs, I made the decision to change the oil in both our vehicles in both spring and fall. I do have a boat that I tow some in the summer with my Tundra but my wife's Mazda CX-5 lives a easy life.

Both vehicles probably around 5000 miles per year each. Overkill, probably, but oil is cheap and repairs.....

I have been using synthetic oil in every engine I own for many years, including lawn mowers and snow blowers.

I always assumed they were simply based on miles driven. If you change your oil and reset the monitor, and assuming the car is programmed for 10,000 miles of oil life, then 5,000 miles later it will tell you your car has 50% oil life left.

Joel9507 has it right


I still don't go beyond about 7500 miles for full synthetic, I do all of the maintenance at home

I change my oil every 5000 miles rather than rely on sensors to tell me when to change my oil. You pay tens of thousands of dollars on a vehicles so changing the oil a bit more frequently than what's recommended makes sense to me and oil changes are cheaper than engine replacements.

I can't speak to the latest ones, but Toyota's maintenance reminder isn't an oil life monitor per se, but purely mileage-based (5000).

As alluded to above, oil life monitors calculate it by how far and fast you drive at a time, how hot the engine gets, etc., via the powertrain control module. Short trips with lots of engine stops/starts (not to be confused with the stop/start systems for fuel economy) and/or the engine not fully warming up are the hardest conditions on oil, followed by dusty conditions, towing, etc. Driving medium to long distances and highway speeds is the easiest. They don't know when you changed the oil, so they have to be reset when servicing. Some car makers make this needlessly complicated, and sometimes shops don't reset them.

Here's a good video about oil life indicators -

https://www.youtube.com/watch?v=t4e0oDBseqo



I followed the video embed instructions from this thread:
https://sigforum.com/eve/forum...610048805#5610048805

but I don't know what I'm doing wrong about the size of the display. Any advice?

I thought it was sensing the differential pressure across the filter, basically telling you when the filter was dirty

^^^ I never heard of this, but Chrysler/Dodge/Jeep/Ram does something kind of like it, notably on the "Pentastar" V6 engine. It monitors oil pressure and temperature via two sensors in the oil filter housing/cooler and calculates oil viscosity. I assume this is factored into the life monitoring.

I mostly do my own maintenance, 4500-5500 miles but I try to stay closer to 4500.

I believe the Audi reminder includes a 1 year timer. We don't drive many miles, and consistently get a reminder based in days, and it is a year since the last oil change.

Ours gets bi-yearly changes regardless of mileage... it's the engine's blood.. so it may be a waste of money but gives me peace of mind to keep them running longer.

Oil changes are cheap insurance.
Using synthetic, like you mentioned you do now, is also a good idea.
A quality oil filter, some thing. There are lots of opinions on that subject. My default is to use Wix or the factory brand if for some reason I couldn't find what I wanted.

Like many, I change oil in my vehicles according to mileage as recommended by the manufacturer. I have a 2001 Honda Accord with 400075 miles on it and it drives just as well today as it did in 2001. I change the oil every 3000 miles and follow all the other maintenance recommendations made by Honda.

quote:

Originally posted by marksman41:
Here's a good video about oil life indicators -

https://www.youtube.com/watch?v=t4e0oDBseqo

So, what the Motor Oil Geek is telling us is that some cars (like GM) have technology to predict oil life (assimilating temperature data, engine revolution data and oil/fuel ratio) while other manufacturers don't and simply use mileage.

Twice yearly. My Wrangler probably accumulates 10k a year now while my wife’s Liberty probably is about 4K a year. Mine is a mixture of short and long trips, hers a majority of short trips.

I use OEM filters and Mobil 1 in both. The wrangler uses the High Mileage oil, it has 147k on it. Hers, actually have owned it eight months longer than mine and it’s under 50k.

7500 in our 3.5TT Expedition
5k in the Mini

I recall GM had an issue with the oil life calibration on a lot of 3.6 V6 [Traverse mostly?] & resulted in a lot of stretched timing chains.

On the Expedition, I use Trip 2 to keep track of oil change mileage.
Mini only has 1 trip meter so I'll be doing it on the 5 & 10k marks on the ODO.

I follow the vehicle’s oil minder. On the 3.0TT Explorer, that’s right around 8,000 miles. On the F350, it’s about 8,000 miles. On the Odyssey, it’s about 8,000 miles. On the other hand, with the Beetle, it works out to be about 8,000 miles. Wanna guess about the Focus ST? Yep, about 8,000 miles.

Truck’s got 165,000, the Odyssey - 120,000. I’ve had five other vehicles I put over 150,000 miles on before I got bored with them, but no issues.

I’ve been using synthetic for 24 years and whatever oil filters. I have no time for 3,000 or 5,000 mile oil changes.

I thought that video showed they would go to zero at the recommended mileage, even if the sensors were not quite there? I thought that was 7500 miles in the video?

Regardless, with synthetic oil, most miles on pavement, little dust, 7,5 seems reasonable.

The type of driving factors in. A high mileage road trip verses short drives in cold weather.

The one mentioned 1 mile trips, Green Bay, WI as an extreme negative example. The 1 mile being to church then the grocery store, different trips.