Background: I have an oil burner 2007 Toyota Camry 4cyl. Unfortunately I took it in on the recall 2 months before the expiration and, of course, it check normal, even though it typically uses 1 quart every 600 to 800 miles. So, ok I just put in oil as it other is a good daily driver. Then I went on a 6k road trip and guess what, used no oil!. Paying more attention I see a big cloud of blue smoke when I start the first time a day so I suspect it is the start and stop of city driving where the oil is used.
Question: Since I am basically doing a full oil change every every 3k-5kmiles, every 6 to 8 months, why bother doing an oil change, just change the filter at the recommended interval? What do you think? Thanks, Tom Arter
I think you know the answer. It's common sense.
#1: Burning oil is not the same as completely draining the crankcase.
#2: I would want to drain out whatever garbage may collect in the bottom of the pan. There are a lot of things heavier than oil...
metal shavings, water, etc.
Since I am basically doing a full oil change every every 3k-5kmiles, every 6 to 8 months, why bother doing an oil change, just change the filter at the recommended interval?
Q: What do you get when you add 1 quart of clean oil to 3 or 4 quarts of dirty oil?
A: 4 or 5 quarts of dirty oil.
Hi there first timer. Interesting question. So your logic is that, on net average, the age of your oil will always be less than the recommended change interval, so maybe you don't need to change it?
For that to work, you would need to burn only the oldest oil first. But that is obviously not happening. You are burning some new and some old oil in roughly equal proportions. So even though the average age of the oil will be less than the recommended interval, you will have a significant portion of your oil that is older than the recommended interval. (maybe one of you mathematicians can give us a mean, median, and standard deviation).
There are also going to be additional factors, like soot, sludge, gas dilution, and so on, that will not be mitigated unless you drain and fill. Quantifying that would probably take empiric observations with an oil analysis.
But bottom line, if you think you can keep the old thing running a while longer, keep doing regular oil changes.
Best.
