2008 Prius - burning oil at 135,000 miles

I would use Toyota full synthetic and change every 10 to 12 thousand miles. I t runs about $6.75 a liter here in Canada and it is probably cheaper in the US. It may use less oil with synthetic? Make sure they don't over fill. Good luck, H

 

welcome to p/c! i would just keep adding oil. why bother changing it if your're continually adding fresh? maybe change the filter every 5000. i don't see why you would need a new engine unless it won't pass emissions, and then, would it be cheaper to replace valve seals or whatever is causing it?

 

This is becoming a common problem. As far as I know, no one has figured out a simple solution. I have been trying different things to see if there is a way to help aside from engine replacement. I only use synthetic motor oil and can assure you it will not fix this problem, at least in a short time. So far I have replaced a PCV valve, put in Sea foam and Rislone (all in different Prii). Marvel mystery oil is next. My Prius does not consume any oil, therefore, I am experimenting with customers Prii and have not had any return yet (don't worry, they will) to monitor the outcomes. In case anyone is wondering these customers are fully aware of the experimentation. I look forward to other members sharing there experiences with this problem.

 

High speed driving can increase oil consumption in some cases. Apparent oil consumption can vary from week to week due factors like temperature, speed, length of journeys and fuel dilution. So you should rightly just average your three fuel logs, which works out about 0.38 qts per 1000 miles - or one quart per 2700 miles.

This is pretty high, but not so terrible to necessarily need a new engine right now. The most important thing is to keep the oil up to it, check it regularly and don't let it get too close to the low level on the dipstick. If you let it get too low then things are gonna go from bad to worse really quickly.

If you give your location (or say what sort of temperatures you're operating in) then it would make it easier to give oil recommendations. I recommend that you try Valvoline Maxlife 5W30 conventional at with about 5000 to 6000 mile intervals.

 

Have you taken apart any of these engines or heard from a dealer who has determined the cause? There was a campaign a while back on the Corolla engines where you would find polished sections of cylinder wall (no crosshatch) and excessive oil consumption.

 

Another thread has 600 miles / quart as a guide for the dealership changing the engine, at least for warranty work-----
Low oil - Red Triangle w/ Exclamation Point | PriusChat

Also some suggestions for oil consumption in above thread.

 

Dave,

Your mileage does seem a little low for burning oil but isn't out of the realm of possibility. If you have been using dino oil I would just keep using that but switch to a high mileage brand. If you have been using synthetic I would switch to a synthetic high mileage brand.

My car, Ema, is burning about a quart or so every 2,000 - 2,500 miles. I don't believe this is becoming a "common" problem as Avi said I just think there are starting to be a lot more high mileage Prii out there. High mileage vehicles will burn oil plain and simple. Esecially those that have a lot of highway miles like Ema. I tried Restore and it didn't do any good with the burn. I may go to a heavier oil in the summer and take the hit to my MPG's but haven't decided yet.

My recommendations as others have posted is to monitor it and add oil as needed. Change the oil and filter every 5,000 miles even with the putting in fresh because most high mileage oils will do some cleaning as well. Whether you want to try a cleaner or not is up to you. I highly doubt any of them will "hurt" but as one other poster said somewhere "There isn't anything you can pour into an engine to stop it from burning oil." So far I have found that to be true. I hope this little bit of info helps.

Happy driving,
Chris

 

With today's engines and oils, especially on a Prius, there is little justification for a 3k oil change interval. It is designed to get you into their service bay more frequently, nothing more. The stealer makes his living off convincing people to over-maintain ther vehicles; that's one reason I am no longer in that business. I use synthetic and go 8k between changes. Since you are using some oil, you may want to stick with dino, but extend the interval to at least 4k, if not 5.

 

Let's see. You are 7/8 of a quart down after 3k miles. I assume this is using 0w-20. I'd switch to 5 w 30 and see what happens -- that might get you to a quart every 5k miles. A quart every 3k miles is not bad at all. I'd just add the oil and not worry. If it bothers you just get your oil changed every 3k with the cheapest oil change and let'r roll.

Oil is cheap. Engines are not. If you get to a quart every 1k miles then I'd start to worry. Doubt you will ever see that happen.

 

As mentioned, keep an eye on it and add oil as needed. Yuor oil consumptiom is not bad as all.

DBCassidy

 

I have not had the opportunity to take one apart. Maybe a look into the cylinder of one of these engines would reveal something?

FYI I have six GenII customers with this problem and zero GenI customers with it, some of them with over 200K on the clock. You are entitled to believe whatever you want, this is what I am seeing.

Avi

 

It would be difficult to see with a boroscope, maybe if you replace one of these you can crack it open.

 

Thanks for the clarification Dave. That was the way I first read it, but it wasn't totally clear. So basically 9/8ths of a quart over 3,900 miles. Yeah it's not ideal, but not all that bad either. It's still easily manageable at this stage, heck my brother's got an Audi that's been using that much since it was new. You just have to keep the oil up to it, top off every week with the amount of miles you drive. Don't let it get down to the bottom quarter range on the dipstick.


BTW. What oil (brand/grade) are you currently using? You may still be able control it a bit with oil choice.

 

I wouldnt replace the whole ICE just because its burning oil. Heck, a quart of dino oil at Wal-mart is $2.49. It would take A LOT of quarts to equal out the cost of a new ICE. And you are burning about a quart every 4000 miles. The oil change interval is 5000 miles. I'd just top off the oil level at that point and extend my OCI to 6500 miles.

Of course, the ICE can be re-ringed and a valve job performed if need be. A new engine doesnt need to be dropped in. The rebuild will be pretty cheap compared to a new ICE....

 

Yep, and if he buys his oil in 5 qt jugs then there will be enough left over to keep it topped off for a 5k to 6k OCI anyway. The extra costs would be absolutely minimal.

 

Not to mention, if you check out the rebates and discounts section over at bob is the oil guy, you can get 5 quart jugs for FREE after rebate all of the time. I have 3-4 five quart jugs of Mobil 5000 that were free after rebate. Dont use them for anything but top-off oil in the lawnmowers and boats but it was free, so who cares

If the OP could get oil that way, then they'd be even more ahead of the game. Top off oil for Prius that burns a quart every 4000 miles for free? Winning.

 

Avi,

Any update on the Marvel mystery oil test or any other "treatment" that helps with the BURN? As I mentioned previously Restore doesn't seem to help, at least in my specific case.

Ema is at about 333K and still burning about 1 qt. every 2,000 miles or maybe a little more. I've found that when you add a full quart or more the burn seems to be a little less rather than just topping off with a 1/4 quart or so more often. It also seems to burn a little less after an oil change. Which seems to indicate the problem is exacerbated by sludge and carbon buildup in the engine and that it is partially cleaned when you replace your oil and filter. So the idea of going back to a 3,000 mile or 3,500 mile oil change especially if you change your oil yourself probably isn't a bad suggestion as some have been told to do.

Look forward to hear how your extensive testing has gone.

Chris