What to do to slow down oil burn? 2010 Prius

[friendly_jacek]

Originally Posted By: The Critic

There's really not a whole lot he can do about the consumption, other than trading the car in. I would just continue adding oil.


This is not correct. Oil consumption can be fixed by repeated piston soaks and oil flushes if caught early. OP was advised about it earlier but ignored the info. Now, at 600 miles/quart, it may be too late and the oil rings could be irreversibly damaged.

BTW, 600 miles/quart is abnormal even by Toyota standards. IIRC, the cutoff is 1000/quart.

 

[ueberooo]

Critic, I'd be very interested in seeing as many UOA's of 0w20 oils over summer runs as possible.

Especially if on extended intervals, and especially for engines that were designed not for very thin 0 and 5w20 oils, but those engines that also permit 5w30s or thicker in the manual. Thanks also for anyone else who can point me to links of these.

 

[xBa380]

Critic,

PCV valve was changed recently. No improvement.

 

[friendly_jacek]

Originally Posted By: ueberooo
Critic, I'd be very interested as many UOA's of 0w20 oils over summer runs as possible.

Especially if on extended intervals, and especially for engines that were designed not for very thin 0 and 5w20 oils, but those engines that also permit 5w30s or thicker in the manual. Thanks also for anyone else who can point me to links of these.



UOA is going to be useless here. How UOA is going to show that oil rings are all gummed up from high piston temps (typical problem in many toyotas)?

 

[xBa380]

Originally Posted By: friendly_jacek

OP was advised about it earlier but ignored the info. Now, at 600 miles/quart, it may be too late and the oil rings could be irreversibly damaged.


I ignored NO info. I had the PCV valve replaced early on after making this post. I switched to shorter OCI's with thicker grade, HM oils... And now I am currently trying various additives. I ignored nothing shy of doing piston soaks and such, which I may do once I get some kreen for the next OCI.

Not sure where I ignored all this info...

 

[friendly_jacek]

Originally Posted By: friendly_jacek

My Corolla started oil consumption at that mark with dino oil every 5000 miles. I fixed it by several treatments with MMO and kreen. Food for thought.


That was posted 10/2012. Almost a year ago.

 

[ueberooo]

Originally Posted By: friendly_jacek
Originally Posted By: friendly_jacek

My Corolla started oil consumption at that mark with dino oil every 5000 miles. I fixed it by several treatments with MMO and kreen. Food for thought.


That was posted 10/2012. Almost a year ago.


That seems like that might help, if it is in deed a gumming up issue rather than rings wearing out.

If using MMO, realize that it might bring down the viscosity grade a whole notch--so, I wouldn't add any large quantity of MMO to a 20 weight oil such that it might make it significantly thinner.

 

[xBa380]

I am trying one thing at a time. Right away I did the PCV... Then Toyota did their oil consumption testing which took two months over the 5,000 miles or so. Afterward, I tried the HM oil and now the MMO. Next is Kreen... I am not going to do every single thing at once.

As far as the MMO, it was added to top off the 5W30 HM oil in there now, not a 20 weight oil. So it should be OK!

 

[ueberooo]

yup I wouldn't mix a bunch cleaning of additives either.

If it turns out to be likely a wear issue instead of a gumming issue, then that means that the tolerances on engine spacings have gone up to older style engines--engines that like it a bit thicker like 5w30 all the way even to 10w40. I wouldn't deviate from the manual a large amount--but I'd run it on the thicker side of suggested (if indeed a wear rather than deposit issue). Also consider some EP additives like MoS2 to slow down future wear and as protection against pistons slapping around a little bit due to tolerances.

 

[friendly_jacek]

Originally Posted By: ueberooo

If it turns out to be likely a wear issue instead of a gumming issue


There is a lot of guessing in this thread. Toyota engines don't have problems with early ring wear. They do have problems with dirty piston oil holes and oil control rings.

 

[blackman777]

Originally Posted By: xBa380
I would say about 1qt every 4K miles or so.
Switch to 4000 mile intervals & you will no longer need to add topoff oil to the engine.

And BTW I would switch to an xW-30 oil as a matter of principle. In countries that don't have MPG ratings for corporations (CAFE) they recommend 0W-30 or even 0W-40 because thicker oils provide a boundary layer to prevent metal-on-metal contact. Since Toyota 0w-20 is made by Mobil, I would stick with the mobil brand. Mobil 0W-30.

 

[blackman777]

Originally Posted By: xBa380
I would say 75% or more of the driving is city on this car.
Flappity flippers! Hold the phone. You are driving 9000 miles in severe service (city)??? I'm fairly certain the manual says no more than 5000 miles in that state, so no wonder the engine started showing excess wear (leaks). Why oh why don't people follow their owner's manuals?

JUST SAY NO TO ADDITIVES. All you do is upset the perfect balance already present in the manufactured oil. Plus it's never been demo'd that additives improve the oil's default state. If you feel the engine needs cleaned of sludge, just run a good synthetic which already-has detergents to do the job.

 

[blackman777]

I can't believe how many people say "Unload the car." Because of 1 quart/4000 mile consumption??? That just means the oil dropped from the "MAX" to the "MIN" line on the oil stick, which is not a big deal.

You will lose $10,000 if you sell your used Prius. That's a major loss of cash. I would just keep driving it until it dies, which is likely 300,000 miles. (I had a car with a blown headgasket and it still went another 200,000 despite that serious damage.)

One final thought: PZEV cars have an extended 150,000 mile warranty in California and the CARB-compliant northeast states. I think OH is one of them. If the car fails emissions inspection, Toyota is required under law to fix the car until it passes
.

 

[buster]

I would try Mobil 1 HM 5w20 or 5w30.