Burning Oil. How to improve.

I recently aquired an '01 Mistubishi Montero Limited w/ 202k miles.
3.5L V6 calls for 5.2 qts of 5w30

I have only had it a short while and put about 1,000 miles on it. I suspected it was burning some oil but does not leak a single drop! Seems to be going through 1 qt per 1k miles.

To those that know better, what is the simple answer here?
Heavier weight oil?
Avoid synthetic (which I have experience leaks easier than conventional - but this is not leaking - though leaking around rings)?

Some snake oil? Which one?

I am not at the point yet where engine rebuild is the answer (which I suspect is the right answer.)

Still drives very well and does not feel down on power.

Synthetics DO get past the rings better.

Given that it is a Mitsubishi engine, my assumption is that the valve guides are shot.

1qt in 1000mi is "acceptable", incidentally, although the catalysts won't like it very much.

Make sure the PCV valve isn't gunked up, clean it or put an OEM one in if it is. You could try 15W40 oil, the cheap house brand stuff will be fine in a gasser, kinda thick in the winter though, use a 10w or 5w in the winter. Snake oils should be avoided.

Sometimes driving it like you stole it for a while will help (loosens the rings up or whatever), I had a car where the oil consumption dropped a lot after a couple months of living in a large city, at 202k it's probably just wore out though.

On the Monteros, valve stem seals are supposedly a common wear item. I am familiar with my gen II montero, but your engine is pretty similar so maybe they didn't fix the valve stem seals by 01?

My fix has been run cheap 10w40 diesel oil until I get around to the timing belt/water pump, when I'll replace the valve stem seals. If it helps I'll let you know in 8k miles

Just went through this on my dodge.

Replaced pcv valve. Switched to 5w40 rotella, i run synthetic in everything and a quart of Marvel mystery oil, the the old italian tune up.

Developed a leak (first on in 300k miles) over the last oil change but i still loss less than a quart in 3500 miles

With the engine good and warm, engine brake down from a higher speed (at high rpm) for a few seconds and then lay into the throttle. See if you can get it to blow a puff of blue smoke. If you can, it's pulling in oil under vacuum, which most likely means valve seals.

I'll look at the PCV in the moring. I'll also give it a big Goose to try to guage how much is blowing.

I'll start with some 15w40 and as things cool I'll go 10w30 and the 5w30 in the coldest months. If I'm burning through it, cheap should be good enough.

Thanks and keep the advice coming.

My old chevy has been burning oil at that rate for about 70k miles, It never occurred to me that I should fix it.

I had good luck in a neon using engine restore in a can from the parts store. It burned 3 quarts in 1k, brought it down to 1 quart per 1k

Was going to suggest the old "Italian tuneup" until I read they are known for the valve seals.

Dusterbd13 wrote: I had good luck in a neon using engine restore in a can from the parts store. It burned 3 quarts in 1k, brought it down to 1 quart per 1k

I'd save this one for the "engine is totally berkeleyed and I'm pulling it for rebuild if this doesn't work" level of issue. I don't think this one is there yet.

Valve seals: fix PCV: fix Rings: ignore, ATF, Italian tune-up, fix

Leak down test? Decent testers are $100+ though.

Years ago (when I was a broke medical resident) I ventilated the block on my E30 due to oil starvation in the carousel at Tremblant. Dropped in a junkyard motor. Compression numbers were uneven and it burned a ton of oil, especially on the track.

I switched to heavier grade oil (15w50 or 20w50) then went a step further by replacing 1 of 5 quarts with Lucas Oil Stabilizer. Oil consumption dropped to reasonable levels: like 1 quart in 3500-4000 miles.

Ran the engine like that for maybe 4 more years without any trouble.