It's a 2020 Jeep Grand Cherokee from a local CDJR dealership with the 3.6L and 25k miles.
On the dealer lot before a test drive and while I was looking it over, engine oil looked clean and fresh, read at the top dipstick mark. Their service department said they change engine oil as part of reconditioning.
Eventually had a PPI done, the mechanic found nothing of concern so I ended up buying it.
After putting on 225 miles in different trips over a couple weeks oil still read at the top mark.
I drove another 400 miles over a period of time before checking again and when I did the oil level was down significantly. Bought a quart of 0W-20 (on the filler cap) and it took almost 2/3rds of that quart to get back near top dipstick mark.
No traces of wetness or soot in the tailpipe, no exhaust smoke after having sat a few days, no oils spots on the ground or anywhere outside the motor I can find, the top of the block around the oil filter cap is clean and dry and the coolant still looks pristine so it doesn't seem to be the apparently somewhat common broken plastic oil cooler problem.
I took it to the same CDJR service department, they said they couldn't find anything so marked the dipstick and had me start a consumption test. Being shocked by so much oil loss in not that many miles I continued checking the level a lot during this test.
Now after driving 800 miles more over a couple months I've seen the oil level gradually go down but just barely, less than 1/8th quart if that.
What most likely is going on?
Thanks!
Might also depend on how long it sits after shutting the engine down
Did you check the oil level on a flat surface using the manufacturer’s recommendation (owner’s manual)?
What most likely is going on?
There are not a lot of choices, the engine is burning or leaking oil. The amount may depend on the way it is driven.
Thanks.
Oil level is checked correctly and the same way every time.
Driving is a mix of town and freeway, and is exactly the same mix in all three mileage intervals I mentioned.
The vehicle sitting or not is exactly the same for all three mileage intervals I mentioned.
The only thing that has changed in the months since I bought it is the oil level and not in an expected way - in the first 225 miles it read full, checking again after another 400 miles 2/3rds quart was gone, in the 800 miles since then around 1/8th of a quart is gone.
Also I don't just check oil level once or twice this whole time, when I saw more than 1/2 quart disappeared I started almost constantly checking, first because I couldn't believe it after nothing changed in the first 225 miles, then out of concern I'd blow the motor if I didn't check to see if level was at least still up to the low mark.
Once I added the 2/3rds quart to get back near full mark I continued to check the level regularly.