Oill consumption and oil weight

The heavier weight would increase friction and lower gas mileage wouldn't it. Well I drove mine adding the quart from 300 to 397 K miles, it did clog my catalytic converter too. I'd say burn it and shop for one of those $600 engines on eBay ? The engineering makes the engine swap a breeze


iPhone ?

 

Assuming you're changing your oil every 10K miles, you're only adding 2 quarts between each change. Using a thicker oil probably won't stop the consumption, so at best it may get you down to 1 quart between changes.

The biggest downside to thicker oil is that it doesn't flow well in cold weather. You appear to be from Texas so we can ignore that.

Also keep in mind that in the old days, when oil changes were done about every 3K miles, your car would count as "doesn't use any oil". When you drive around with a case of oil in the back seat, then you're consuming oil.

 

People always seem to forget this when they start complaining that their Prius is the only car they've ever owned that consumes oil.

Anyway, the loss in fuel economy is a drop in the bucket when moving up a grade or two in oil thickness. You'll likely not notice a difference. I'd start with high mileage oil and see if that improves things before ramping up thickness. 10w30 will be fine.

 

Me, I'd change the weight first, use high mileage as last resort. The high mileage oils will swell seals, it's somewhat akin to putting the car on methadone maintenance: if you go back to regular oil the seals will shrink back and oil consumption will likely skyrocket.

 

Mendel is a veteran of this board and I'm not, so take that into account, but I'll respectfully disagree. Heavier oil will have slightly more trouble passing through the small holes and spaces in your engine, and high mileage oil (at a lower viscosity) will not. That makes high mileage oil a slightly better choice for lowering consumption while still protecting against engine wear.

On the other hand, Prii with engines identical to ours come with a Toyota factory recommendation for heavier weight oil than the U.S. Prius does. This has been discussed on other threads here, but the short version is Toyota is legally obligated to recommend the same weight of oil that it uses when certifying the car's EPA gas mileage, and Toyota runs lightweight 0w-20 oil in order to eke out every last bit of reduced friction to get a high number. So, 10w-30 is not that far from what Toyota admits elsewhere is an appropriate oil weight anyway.

Personally, I'd try the high mileage version of 5w-30 oil first. If it works, just keep using it forever. Based on the results others have reported here, I'd hope for some improvement but expect something less than a miracle.

 

I switched to 5w-30 full synthetic about 30 k miles ago to quell oil consumption on our 2010 Prius II that now has almost 151 k miles on it. I was (key word) consuming at a rate of a quart every 4,500 miles. I then switched to thicker oil, drive a little slower (5-10 mph over the limit rather than 10-15 mph) and have used an engine flush and oil additive to the fresh oil.

I have a little over 9 k miles since the last oil change and have consumed 20 ounces .

Next oil change is going to be BG Products EPR flush prior to draining the old oil, then Pennzoil Pure Platinum 5w-30 full synthetic with BG Products Extended Life MOA. Hopefully done on Saturday the 25th, but we'll see if that is in the cards or not.

 

Engine flush is BG Products EPR:


Put this in prior to draining the engine. Run the Prius for about 10 minutes in "maintenance mode" at idle. Drain the oil. You'll see a much deeper black than usual.

This is the oil additive Extended Life MOA:

Supposed to help keep the oil basic and help fend off the affects of gas contamination in the oil creating an acidic environment.

I also use their 44K once a year as a fuel system cleaner:


Here's a thread where I shared some info from a BG Products rep in regards to the above Products:

[POLL] Excessive Oil Usage

Hope that helps and answers your question.

 

You can search maintenance mode and it will return results. It invloves a "chicken dance" but not that hard to do. I wrote the instructions down and keep it in the glove box when needed (along with "invalid mode").

Maintenance Mode allows the engine to run like a normal car. You shouldn't drive the car in this mode. This can be beneficial for many different reasons.

Keep us posted

 

Hello, can you report back? Did you every try the 10w30? How did it work? I was wanting to try 0w30 but might not be able to find it. I'm unsure about changing the colt number of the oil weight.

 

I'd try a bottle of Auto-Rx Plus $23 and see if it frees up the rings and cuts your oil consumption.
Toss a bottle in your next Oil Change drive for say 4K-5K miles and change the oil and filter.
I have an old Volvo 960 with a 2.9L I6 135K miles that was starting to use some oil like 1/2 quart every 1000 miles. I did the Auto Rx thing and so far in the last 1000 or so miles I'm not using any oil. I have about 3000 miles on the 4000-4500 mile cleaning phase.

They say use two bottles but with the 1.8L only taking 4 quarts I'd recommend using one bottle. My Volvo uses 6 quarts and I still only use one bottle every 65K miles.