Castrol Syntec 5W/30 '02 Prius Hybrid UOA

[Simeon]

Here is a VOA & UOA of Castrol Syntec 5W/30 (purchased Feb '04) done by Blackstone Labs 6/25/04
Auto is 2002 Toyota Prius Hybrid (1.5L 4-cyl gas/electric) used in southern California and driven about 15K miles/year with a fair number of short trips (5-15 miles). I started using synthetic oil at 14K miles. My biggest concern was gas/oil build up due to the hybrid gas engine starting/stopping many times and the oil not getting hot enough to boil it off adequately. The UOA was on a sample with 5,826 miles & 4 months service ( 0 qts. of make-up oil added) using the factory recommend Toyota 90915-YZZA2 oil filter. I currently have 40,500 miles on the engine with a lifetime gas consumption average of 41.8 mpg.

Castrol Syntec 5w30 VOA / Castrol Syntec 5w30 UOA / Universal Averages
Aluminum 0 / 3 / 3
Chromium 0 / 0 / 1
Iron 1 / 5 / 8
Copper 0 / 1 / 3
Lead 0 / 0 / 2
Tin 0 / 1 / 1
Molybdenum 32 / 34 / 24
Nickel 0 / 0 / 0
Manganese 1 / 1 / 1
Silver 0 / 0 / 0
Titanium 0 / 0 / 0
Potassium 0 / 1 / 1
Boron 46 / 21 / 25
Silicon 9 / 7 / 8
Sodium 1 / 4 / 4
Calcium 3013 / 2906 / 2066
Magnesium 4 / 4 / 200
Phosphorus 775 / 677 / 715
Zinc 792 / 728 / 814
Barium 0 / 0 / 0

SUS Viscosity @ 210*F 61.6 / 59.7 / 57-63
Flashpoint in *F 410 / 350 / Water 0 / 0 / Insolubles % 0.0 / 0.2 / TBN 9.9 / 2.2 / ?

"Blackstone's Comments for Virgin Oil: ...Silicon was mildly high at 9 ppm. This is fairly high for a virgin oil, though it is probably from anti-foaming additive rather than dirt contamination and should not cause wear problems. The TBN read at 9.9. This is a strong reading and shows the new oil starts out with plenty of active additive... Viscosity was good. Molybdenum, phosphorus, and zinc are anti-wear additives. Boron and calcium are detergent/dispersants.
Blackstone's Comments for UOA: No problems showed up in the initial sample from your Prius. All wear read at or below averages for this type of engine, which is a good indication of normal wearing parts and careful operation. The universal averages show normal wear from this type of Toyota engine after about 5,700 miles on the oil. Insolubles were low, showing good oil filtration. Minor fuel dilution was found, though not enough to worry about. It is likely due to the short trips. The viscosity was still good and the TBN was okay at 2.2. A longer oil use should be fine. Try 7,000 miles."

Based on the results shown here and reviews of other synthetics reviewed, I will probably be using another manufacturers oil next change. I haven't made up my mind yet other than I'll probably stick with 7,500 mile change intervals.

Thanks, Simeon

 

[JustinH]

Looks like a good candidate for mobil1 0w30, or 5w30.

JH

 

[SSDude]

The wear numbers look good but this oil has had it. The TBN is down in the danger zone after 6,000 miles.

 

[Al]

Nice ...Is there any value given for fuel dilution. With that low flashpoint it is probably on the high side. That may be typical with many starts. But it could also mean you have perhaps a leaking injector.

I think you would be better off with Mobil 1 but if that fuel dilution is typical perhaps go with a conventional oil and change more frequently (to save some money) .

Anyway-thanks for posting.

 

[Simeon]

Fuel Dilution:

The UOA figure was 0.2. I slipped up and overlooked it in my initial posting.

 

[Ken4]

Off topic:

Do you calculate your gas mileage by the (distance travelled) / (amount of gas used) at every fill-up?

I ask this bcos a local owner reports only 15km/L for his 2004 civic hybrid. Manufacturer's spec is ~30km/L. At every traffic light, the AC cuts off, so he puts in back into N to get the AC working again.

 

[jthorner]

Those are good wear numbers. I wouldn't be too quick to switch away from Syntec. I know that it is bashed on theoretical grounds here, but I just posted a UOA on my Volvo with Syntec 10W-30 today and it performed very well.

John

 

[Whimsey]

quote:

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Originally posted by SSDude:
The wear numbers look good but this oil has had it. The TBN is down in the danger zone after 6,000 miles.

---

With Blackstone a TBN rating of 1 indicates worn out. They use a different testing method for TBN than other labs. Otherwise your wear looks good and as Blackstone said you still had life left in the oil and could have gone further with this oil.

Whimsey

 

[T-Keith]

Just out of curiosity, how many of these miles were run with the engine off? Probably not alot, but it would contribute

-T

 

[Simeon]

My gas mileage on the Prius is calculated using miles traveled vs fill-gallons pumped. This truer figure is usually about 2-4% lower than the digitally calculated trip mpg figure that is displayed on the console readout.

I'm unsure of how many miles I've traveled under pure electricty (gas engine off) vs with gas engine running, since the car switches back and forth seamlessly and it's is not really under the control of the driver. I'd estimate that probably only 10-15% of the miles traveled would have been pure electric. I've occasionally thought about trying to integrate a Hobbs meter to measure the gas engine run time but obviously never gotten around to it.

Thanks for your comments, Simeon

 

[Simeon]

Re: Whimsey's earlier reply, I should have stated initially that this UOA was a sample and I'm continuing to use the oil. I'll change and re-submit at 7,500 miles.

Also, I now note that I overlooked initially posting UOA properties for both Fuel% and Antifreeze%. The figures were 0.8% for Fuel%, and 0.0% for Anifreeze%.

Thanks, Simeon

 

[buster]

TBN of 1 in a Toyota is bad as we know most oils show good results. Again, $5qt for this?

 

[Cutehumor]

Buster, you seem to be pointing out all the syntec UOAs with low TBNs. hmm..I wonder why..

 

[buster]

I'm honestly not trying to start a fight. I'm just pointing out that so many on here are so concerned about a few ppm difference in wear, and complain that M1 is over priced. However, if one looks at most (not all) US Syntec UOA's you'll see the TBN is very low. To me, a $5qt oil should hold up longer if need be.

 

[Bill in Utah]

quote:

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TBN of 1 in a Toyota is bad as we know most oils show good results. Again, $5qt for this?

---

TBN was 2.2

I agree no one should pay $5 a quart for oil.

If it was me, I'd go with Castrol Blend for $2 or Dino and change it out at 5000 miles.

Your engine will not notice a difference.

Report looks ok and good lifetime MPG.

My Corolla is real close to your MPG with 41.6 overall for 36k miles.

Take care, Bill

 

[ToyotaNSaturn]

I agree buster, $5/qt is too much for this. Not a bad UOA at all, but it's hard to justify the value in this product given it's price IMO. But it did protect the engine quite well all in all.