Now that we are going 6k, 7.5k or even more, we check in between changes more often and discover the bitter truth ... all engines consume oil to some degree.
This is a good point for people who just drive their cars (which could be considered a majority in some circles) However I have had roughly 60 vehicles in my lifetime, including tractors, large trucks, vans, suv's, etc. and I have always monitored oil consumption.
The truth of that is that oil consumption varies for sure, but are generally considered the exception and should never be classified with abnormal oil consumption.
Here's what the manual on my new 2014 Outback says,
" If the oil consumption rate seems abnormally high after the break in period, for example more than 1 quart per 1,000 miles, we recommend that you contact your Subaru dealer."
This insults people's intelligence and if accepted gets Subaru and others off the hook. As you can see by this statement that if you change your synthetic oil at say 7,000 miles, you could effectively have put in double the amount of oil.
Is this acceptable ? Of course it's not!
Again it is of no surprise to me that vehicles will use oil ( no matter how long it is between changes)....again a quart BETWEEN oil changes would be acceptable to me. Anything in between is abnormal..... especially on vehicles with less than 50,000 miles
add; 90% of the vehicles I have owned, simply have never used oil. This tells me the engineering is correct. Ones that use a quart (more or less) every 2,000 miles are essentially failed engineering and falls into all other myths about oil consumption, changes, and flat out falsehoods that the industry projects.
Regular oil vs synthetic? Still deciphering what is fact and what is myth. (and this debate will be ongoing), but if you follow the money, and add in some politics you will definitely become skeptical.
I have a 1996 Geo tracker with 243,000 miles on it. Never been rebuilt, still has great compression, no engine noise. I changed my oil/filter (conventional oil) every 5 to 6 thousand miles, sometimes longer. The manual says 5,000 miles and filter every other (Somehow this myth about 3,000 mile oil changes got out to the public and was left unchallenged. The proof of the matter was that good quality oil was still viable (even when it was black in color) beyond even 7,000 miles. But common sense (since most of us don't have our oil tested) says we lean towards being safe than sorry.
Here is a quote from Edmond's
Myth: You Should Change Your Oil Every 3k Miles Because Carbon Will Build Up Due to Blow by
Truth: Carbon is not a big problem when it comes to oil change intervals. But don't take my word for it, here is a statement by the guys who actually test used oils. "Carbon isn't usually a big problem. Most of the time it's big enough the oil filter catches it." Ryan Stark Blackstone Labs
"The fact is, a good oil filter will catch and filter out any carbon that may enter the engine. A good oil, will suspend contaminants and allow the filter to catch them."
So as I see it we still have questions and the answers often come from the wrong sources (the oil, auto, and jiffy-lube industries) We have forums like these, to lend some information out to the consumer so we might be able to make better choices.
Yesterday I added a quart of oil to my brand new Subaru Outback (970 miles)