Which oil do you prefer?

I like the M1 0w-20 and the Ultra Pennzoil Platinum oils.

I got bored with 0w-20 and put in 5w-20 UPP last oil change.

 

Notice any mpg impact?

 

How does one become bored with oil?

Why is it so hard to follow what the manufacture recommends?

 

It's winter time, so it's hard to tell. I've also been putting in 10% ethanol, and I idle a lot before I go into work. I've gotten over tracking my mpgs to the tenth of an mpg all the time, but still enjoy getting better than the 10mpg I get in my truck.

But with this cheaper gas I can afford to drive my truck more. Yay!

How do I get bored with oil? Because I'm adventurous, and I like to tweak the OMG!!!HE'S DEVIATING FROM THE TOYOTA SCRIPT!!!! types. Recall if you will, that the car is rated for any oil up to 50w depending on the ambient temperatures of your location and the availability of local oil weights. I won't use 50w, but I could if I felt like it.

Hard to follow instructions? No. I just wanted to use a 5w. Rest assured, however, that the hot viscosity numbers for the 5w-20 that I used sits comfortably within the range of the 0w-20's that people are using.

 

This car was engineered by Toyota to run on 0W-20 full synthetic oil for optimal engine performance and fuel economy. It is required. The manual states "If SAE 0W-20 is not available, SAE 5W-20 oil may be used. However, it must be replaced with SAE 0W-20 at the next oil change."

0W-20 costs about $27 for 5 quarts and is available at any auto parts store. Every brand makes it in 2015. There is no circumstance I can imagine where you would be stuck somewhere and have no choice but to use 5W-20, and if that were the case, Toyota says it "must be replaced" with 0W-20 at the next oil change.

Final comment: if you must put in the wrong oil such as 5W, keep in mind this will make it harder for the engine to start in cold temperatures. No matter how you look at it, it's the wrong choice!

 

That sounds a bit authoritarian; who actually owns the car? There's not a major difference between the lubrication requirements of most cars, therefore there's no "wrong oil," only a recommended oil. Because Toyota wants your car to last a good long time and get good mileage, they recommend the best possible oil, and currently that is a 0W20 synthetic, both for reducing engine-wear and for improved fuel economy due to the lower viscosity.

Any manufacturer who would deny a warranty on the claim that the "wrong oil" was used, would have a tough time defending it in court, provided it was an engine oil certified for automotive use.

 

NJP, you are incorrect. I'll let you find out why on your own.

 

To keep things really simple for us dummies, they recommend the same 0W-20 for all locations and all seasons, whether Texas in the summer or Alberta in the winter. A 5W- XX or even 10W-XX oil has lower viscosity at moderate temperatures than 0W-XX does in extreme cold. Why exactly is it so horribly "wrong" to use the 5W-XX or 10W-XX at moderate or high temperatures?

 

If it hasn't been mentioned, in Oz the oil grade recommendations in the Owners Manual are much more traditional, suggesting a gamut of heavier multi grades are all ok.

 

Nothing is "horribly" wrong.

0W is synthetic, and is better for the engine than a non-synthetic 5W or 10W if you're using the Toyota recommended service interval. Let's face it...why do people want to switch to 5W and 10W so badly? Most likely because of cost. You can find those oils cheaper because they come in non-synthetic. If you're running 5W or 10W synthetic, then it's going to cost about the same as the Toyota recommended 0W, so why use something other than what the manufacturer recommends? If you use a non-synthetic 5W or 10W due to price, you should not be using the extended service intervals. This means changing the oil more often. Is this saving you money?

Most engine wear occurs at start up in a cold engine. 5W and 10W are thicker at ambient temperature, and take longer to circulate. Potential for accelerated long-term wear.

Modern engines fighting for MPG use low-tension piston rings. heavier weight oils tend to make it past the rings and into the combustion chamber easier. Some cars using the heavier weight oils develop an oil use "problem," which can sometimes be remedied by switching back to the 0W. This is not exclusive to the Prius.

Fuel mileage. In most cases, a 0W will be thinner at operating temperature than a 5W or 10W, and give better fuel mileage. That's what the engineers (SAE) say. Your results may vary.



We use only OEM certified oil in vehicles. In this case, Toyota 0W20 in Toyota cars that call for it, and change it at factory recommended intervals...for 20 years now...and have never had a properly serviced engine go bad for lack of oil changing. That's 1 year or 15,000km in Japan, which is ALL severe condition driving (stop and go, short trips). I'm a member of SAE, and iATN; automotive engineers, and the vast majority of top-end vehicle repair facility owners back me up on this point. There have been some problems with some cars with oil monitors (BMW and Chevy come to mind), and the manufacturers updated the firmware to change this. The myth that the manufacturers just want engines to wear out, so you have to buy a new car, is just that: A myth. Unfortunately, there is a glut of uneducated auto technicians in the US who perpetuate it, their only reasoning being "because that's how it's always been done." Oil and engine technology is moving forward at a blinding pace. This is not the 1980's.

The whole thing with the "what oil" debate is really baffling... I can't think of a single reason, backed up with scientific reasoning, to deviate from what the manufacturer of car a recommends you use in it. Toyota is easy, as they just call out for API SJ 0W-20. BMW you need something with the LL01 certification, and GM you need something with a Dexos certification. Keep in mind that "Meets or Exceeds" is not certified. Why people insist on deviating from this, citing anecdotal garbage as reasoning...is a mystery.