After a 1660 mile trip in Xmas week, 95% of it was on I-75, I found the oil was 1/5 of qt too low. What puzzles me is that the tail pipe is very clean, absolutely no black stuff, and I just changed the oil on 11/7. Right before the trip the oil was right at F. Any idea why the tail pipe is so clean? If what gone away was water or unburn fuel, but there shouldn't be that much in newly changed oil. Any thoughts?

 

This is what really puzzles me. If this were my vehicle, I would be concerned about why the oil level was so low? For example:

1) Between the oil change and the beginning of your Xmas week trip, did the car seea lot of short trips in colder air temperatures?

2) Between the oil change and the beginning of your Xmas week trip, how many miles did the car see?

No. Sorry.

 

Leaked not burned? Catalytic converter does a good job of burning off small amounts of oil burning. Was the original level taken just after shut-off or after sitting? Was second level taken just after shut down? Year, engine, miles?

 

Sorry about the lacking of details. It's a 02 V6 with 55309 miles on it, no oil leak at all, never burns oil, only a little rust trace in the tail pipe, having been driven mostly in town for my wife's daily commute to work (6 miles one way). The oil change before the recent change was 6 months ago, then the clock was about 3500 miles less. Actually the latest one was done two weeks before the trip, all the measurements were done at about a hour after driving, as the engine still warm but oil should have flowed back to the pan.

 

Not sure where you're located but if it has cold winters then that type of driving is the worst you can do for an engine as there isn't enough time to burn off wtaer vapor. Anti-freeze level ok? Old oilhave a milky appearance?

 

We live in South Fl, it's rarely below 50 degree. Coolant and old oil looks normal. I'll keep eyes on it.

 

Well,it appearsthat the somewhat shorter trips (i.e. 6 miles at a time)are at least partially to blame. However, Ido not believe that just two weeks of these short trips in moderate (i.e. south FL) temps plus the highway driving on your trip is enough to fully explain the apparent loss of that considerable quantity of oil.