My impression of 4,102 mile trip

Just returned home last night from an 8 day, 4102 mile trip. States included Iowa, Missouri, Arkansas, Kansas, Colorado, Wyoming, Montana, Idaho, Washington, and South Dakota. The first part of the trip was to pick up my son at the airport in Kansas City, drive down to Table Rock Lake and enjoy 3 days of slalom and barefoot skiing. The rest of the trip was to get his vehicle out of the airport parking garage in Spokane, Washington, spend a couple of days in Idaho at his place, and then come home.

I was expecting somewhat poorer mileage with the Prius since I knew we would be moving quickly on the Interstate. Before starting out on the trip, I blew the tires up nice and firm and dropped the 0W-20 oil and put in 5W-30. The cruise control was set on 80/81/82 mph a lot of the time in Kansas, Colorado, Wyoming, and parts of Montana. I also cruised 75-80 mph much of the way home across South Dakota. Overall mileage for the entire trip was 47 mpg. This was 2 or 3 mpg better than what I would have guessed before leaving. Temperatures ranged from 104 degrees (day-Kansas) to a low of 54 degrees (night-western Montana). We used the air conditioning almost all the time, although the cooling system is so good on the Prius, the fan was usually set on it's lowest setting.

Gas prices varied widely. The highest paid was $3.67 per gallon, the lowest was $3.09. Hat tip to southern Missouri for having cheap gas! The entire gas bill for the 4,102 miles was $301.00. Absolutely amazing to me.

This was the first time that I really used the "B" engine brake mode. It performed wonderfully and prevented a lot of brake pedal use, except on the steeper grades. It appeared that using "B" would provide enough braking force to control speed, except on grades approximately 6 percent or greater. My son was intrigued with that, and quickly caught on to using the "B button" instead of the brake pedal.

Something I hadn't counted on was using the "Power" mode to speed up accelerator pedal sensitivity while in the mountains. It made driving in the mountains more comfortable by reducing pedal travel and the amount of work needed from my right foot.

Road noise and the sound of the Atkinson cycle engine did not bother me but my son did comment on it a few times. Maybe I had just gotten used to it. I would say it was "noticeable" but not a "nuisance".

My condolences go out to the Prius owner that got hit, just north of Denver, on Sunday, July 7th, in the late afternoon. A genIII Winter Grey Prius hatchback got rear-ended by a full size pickup truck pulling a horse trailer. The wreck pancaked the back of the Prius and made it undrivable. Very sorry to see a fellow traveler end up in a situation like that. It appeared that all humans and horses were without serious injury.

All in all, a wonderful trip.

 

I put a little heavier oil in it because I knew we would be running 80+ miles per hour for long periods of time. I'm guessing we likely put 900 - 1,000 miles on her going over 80. That is why. Did it make any difference? Probably not, but I felt more comfortable, especially during the 104 degree temps across Kansas. I'll drop the 5W-30 and put 0W-20 back in this Fall.

My main concern was not fuel economy.... otherwise I would have driven 65 mph (or less).

 

Mpg was calculated. The Prius was telling me it was 49.x (almost 50), but I kept track myself. Even at 47 mpg, I was impressed.... but at the same time, if 1,000 miles were at 80+ mph, that still means that 3,000 miles were slower than that.

I respect those that comment on the oil change. I don't doubt that it likely made no difference at all, other than my own personal feeling. As an engine builder in a past life, that 0W-20 just strikes me as being "water" and I'm apparently just getting old and set in my beliefs. As stated above, when the weather cools down, I'll put the 0W-20 back in.