200k mile 2005 Prius - Traveller 15w40 CJ-4/SN - 6500 mi

[atomix8]

Car is driven mostly highway, with the usual metro DC traffic at times. Then the engine gets to take a nap. Most of the time it's howling along at 70 mph.

I couldn't wait to do this UOA. The owned-since-new family Prius started burning oil somewhere in the 100k mile range. Got to be about 2 make up quarts within a 7500 oil change interval, on a car with a ~3.5 quart sump. Had run 5w30 synthetic in it forever, switched to 'high mileage' -- no change. Put in conventional -- no change. Owning two diesels, my eye quickly turned to the
Cheap WIX oil filter used, the slightly bigger one for Camrys.

Yes, this is way too thick for an engine that Toyota specs for 0w20 in later years. But the wear metals seem to say all is ok. Guess the parts are barely touching anymore ;-) ?

Not sure what to make of the Sodium, low enough to not worry?

 

[csandste]

How much was gas mileage affected?

 

[jakewells]

It looks nice you could have went 7500 miles on that sample and the sodium could be from the previous oil in the sump. According to PQIA sodium is at 7 ppm with this oil but the sample is old. http://www.pqiamerica.com/May 2013/traveller.htm

 

[JLTD]

This is super interesting… Waiting for feedback

 

[dnewton3]

Can easily double your OCI with that kind of wear.

Side discussion ...
I'm not that familiar with the Prius, but it's a hybrid, is it not? So how many of these miles is the engine actually running? The wear rates may need to be adjusted for the actual engine-driven miles?

 

[paoester]

Toyotas and Scions have had oil ring sticking issues over the years. If you get super serious about it, get this stuff: https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/5232562/1
but it is spendy. What you've done, by repeatedly using a diesel engine oil, might have already cleaned the ringlands to some extent. That Valvoline in the thread is meant for 1 oil change only, not to be used all the time, so maybe worth it when it really scours out the rings.

Great run. No problems. You will lose about 2% MPG compared to running, say, Pennzoil Platinum 5w30 here, due to the extra hydrodynamic viscosity drag from the 40 weight. Not much to worry about.
The kind of tires you run, and their pressure, will have around a 4% variation, something in that area, for comparison.

The sodium is not from coolant leaking into the oil is the good news. If it was, potassium would also be high. Its probably just from some additive in the oil, or leftover like somebody said above.

Originally Posted by dnewton3
Side discussion ... I'm not that familiar with the Prius, but it's a hybrid, is it not? So how many of these miles is the engine actually running? The wear rates may need to be adjusted for the actual engine-driven miles?
A good rule of thumb is the % of engine miles in a run is about the same as your highway miles percentage in the long run. For example, if this car sees 70% highway, stop-n-go for the rest, then it is around 70% engine-on miles. The math works out to that usually. -- During city driving, the engine hardly puts on many miles at all, typically only running in bursts of acceleration. On the highway it will turn off when going downhill, even on a slight slope, or when slowing down a bit, but that is about all the rest it gets on the highway.

 

[pandus13]

OP,
first you are very courageous.
This is why, for the fun factor, I would post this in the priuschat forums.

Boy, Those comments would be fun.


Second, don't mind Dave Newton. He changed his conventional oil at 10k-15k with successful results. If we did what he is asking of us, we would all need not go into OCD mode and we could actually save the environment...Without eating kale chips.

third, From my memory from the prius forums, I think you may need to look at the Prius's version of PCV assembly to clean it, instead of the cylinder soak

 

[krismoriah72]

210K miles.. you talk about doing a plug change? has one already been done or are you on the first set?

Would love to see those pics after all that consumption.

That traveller oil is rated SM i believe so you are still within the realm of dual rated.

I dont see the myth about thinner oil decreasing wear at startup... doesnt that engine start many times during a driving cycle?

 

[atomix8]

Originally Posted by pandus13
OP,
first you are very courageous.
This is why, for the fun factor, I would post this in the priuschat forums.

third, From my memory from the prius forums, I think you may need to look at the Prius's version of PCV assembly to clean it, instead of the cylinder soak


Haha, I'd like to see that priuschat discussion too, but then I'd have to join that forum

I replaced the PCV at the 120k mile service, but that's a good thought. Could be a culprit as well.

Just glad the consumption slowed/stopped as this is my wifes car, and she never checked the oil level.

 

[atomix8]

Originally Posted by krismoriah72
210K miles.. you talk about doing a plug change? has one already been done or are you on the first set?

Would love to see those pics after all that consumption.

Yes, did plugs already at ~120k. We'll see if we keep the car to 240k, though nothing is really wrong with it! Have all the parts for the 240k service. Maybe $90 worth, such a cheap car to maintain it's unbelievable.

 

[zorobabel]

Surprisingly, the Prius sheared that oil to almost a 30.

 

[CR94]

Originally Posted by dnewton3
... I'm not that familiar with the Prius, but it's a hybrid, is it not? So how many of these miles is the engine actually running? The wear rates may need to be adjusted for the actual engine-driven miles?
Bear in mind that the miles the engine is not "actually running" are substantially the same miles the engine of a non-hybrid would be running under very light (or zero) load.

 

[tundraotto]

Originally Posted by CR94
Originally Posted by dnewton3
... I'm not that familiar with the Prius, but it's a hybrid, is it not? So how many of these miles is the engine actually running? The wear rates may need to be adjusted for the actual engine-driven miles?
Bear in mind that the miles the engine is not "actually running" are substantially the same miles the engine of a non-hybrid would be running under very light (or zero) load.


^YES - and when the hybrid engine is running - it's likely to be running at a relatively high load to charge battery etc.

As far as the report - looks GREAT to me.

 

[CR94]

Originally Posted by tundraotto
Originally Posted by CR94
... Bear in mind that the miles the engine is not "actually running" are substantially the same miles the engine of a non-hybrid would be running under very light (or zero) load.
^YES - and when the hybrid engine is running - it's likely to be running at a relatively high load to charge battery etc. ...

Yes, and the engine is smaller than usual in proportion to the weight of the car.

 

[paoester]

Originally Posted by tundraotto
^YES - and when the hybrid engine is running - it's likely to be running at a relatively high load to charge battery etc..
Correct, these engines are most efficient when running at around 80% full torque load at about 2,000 rpm.

 

[dnewton3]

Originally Posted by paoester
...
Originally Posted by dnewton3
Side discussion ... I'm not that familiar with the Prius, but it's a hybrid, is it not? So how many of these miles is the engine actually running? The wear rates may need to be adjusted for the actual engine-driven miles?
A good rule of thumb is the % of engine miles in a run is about the same as your highway miles percentage in the long run. For example, if this car sees 70% highway, stop-n-go for the rest, then it is around 70% engine-on miles. The math works out to that usually. -- During city driving, the engine hardly puts on many miles at all, typically only running in bursts of acceleration. On the highway it will turn off when going downhill, even on a slight slope, or when slowing down a bit, but that is about all the rest it gets on the highway.

I see that as plausible; probably no better or worse than any other guestimate. That being the case, we'd have to know how many miles of this UOA were city versus highway miles. OP ???

 

[atomix8]

70% highway is probably about right, not getting much benefit out of the hybrid most of the times. ~20 mile commute one way.