Hey all,
I have a 2007 v6 4Runner with about 116k. I got this rig about 1.5 years ago. When I bought it (at 98k miles) the previous owner had just changed the oil so it looked all clean. I've noticed since then that over the course of 5k miles the oil level on the dipstick goes down about halfway or maybe a tad more. As a note, at about 3k miles the oil drops halfway then it stays around that spot for the remainder of the time. I'm guessing it's burning off.

Is this something I should be concerned about?
Is this sign of prior abuse?
Should I worry about topping up to the full mark when it drops?
Should I address this before it gets worse and what would the repair typically be?

As a side note my mechanic did a pre purchase inspection and noted no oil leaks. I see no smoke at startup either.

Thanks

Change the oil every 5k.
Use the same kind of oil and filter each time.
I like to use Mobil 1 in the 5 quart jugs because I put all my used motor oil back in there and use the indicator window on the back of it to measure how much oil is coming out. If you are losing more than a quart of oil over 5k i would say that is excessing. if you don't see any leaks, then your oil must be going somewhere. most likely scenario is that you are losing it past the rings on your pistons. not a whole lot you can do about that. if it drives and runs good, that may just be your lot in life. if you get too much oil past the rings, your motor with start to run bad and the tail pipe will smoke.

Another thing you can do it check your sparkplugs for discoloration.

You really need to diagnose the problem to get an idea of what's going on with your motor. When I was shopping for a T4R, I noticed a lot of 1GR FE's leaking oil at the valve cover and timing cover. Check your PCV valve too. Easy to access and check. May be getting blow by.

I'm the type of person to note how much oil is lost, then top off when I see it. Keep it topped off.

Good luck with your rig. Hopefully you get it diagnosed.

I second the PCV valve idea. It may or may not be the problem but it's so cheap to replace that there isn't any good reason to let one sit in there for long enough that you really even have to question whether or not it's still functional.