[Rmarchena]

If you observe carefuly, the expended miles in any car does not represent all the stress that the engine experiments. All of us use the mileage as a basis and is wrong. You never can be accurate about the right time to change your oil and other parts according to miles. Instead, if you start changing your oil after 30 or 40 hours of driving time, you will conserve your engine properly.
The Prius is an special case but not an exception. Measure its driving time and service it accordinly.

 

[LouieNet]

Measure its driving time and service it accordinly.

Interesting proposal. I'd like to submit that driving time should be included, but not used solely, in the calculation of how to best service the vehicle. Consider this:
One hour of 60 miles per hour driving causes more stress to the engine and uses more oil than one hour of idle time.

At the same time, I believe your point is: one hour of idle time will generate some amount engine use (all be it not so much in the Prius engine than that of other cars) even if you are not traveling any miles. Therefore, the car should be serviced if the car is left idling for some amount of hours even if it hasn't traveled.

Did I get the gist of your statement?

Louie

 

[Rmarchena]

you got it

You got it...

 

[Rmarchena]

Maintenance Criteria

Maintenance Criteria:

Per hour:
1. Oil lubricated engines and parts
2. Electric motors and parts
3. Batteries and cables
4. Lights

Per mileage:
1. Axels and joints
2. Tires and rims
3. Transmissions and parts

Per inspection:
1. Break pads and fluids
2. Filters
3. Wipers
etc.

 

[LouieNet]

You will want to add another section for items that breakdown even from non-use. For instance motor oil needs to be changed some time between 6 months and 12 months, I believe, even if it's not used. Even the rubber on the windshield wipers will disintegrate with time.

So is that what you mean already by "per inspection"?

Louie

 

[GlacierBobby]

Aren’t hours used as the criteria for aircraft maintenance? But then airplanes spend most of their time flying whereas each Prius owner has a different ‘duty cycle’ of usage.

 

[Phoenix]

Maintenance -- Hours instead of Miles

Airplanes, like boats, are under full load nearly the entire time the engine is running. Cars are under light load (on level ground) or coasting a good part of the time. Lift your foot of the accelerator pedal on your Prius and see how far you go compared to pulling the throttle back on a boat.

Also, a lot of other things in cars are wearing out when the engine is running, like the transmission, wheel bearing, tires, etc. Boats and cars, not so much (though they tend to rot into the ground just sitting).

That's why boats and planes have hour meters, and cars have odometers.

 

[RSnyder]

You should add a "per breakdown" category for things that will break in such a low percentage of all Prius that it's not worth checking or replacing ahead of time. Some should/could be computer monitored:

per breakdown (rare)
electric motor/generators
electric wiring
A/C motor
computers (per TSB until the software is good)
timing chain
transmission (except for lubricant which should be per mileage)

per computer monitoring
HV battery
12V battery (wouldn't that be nice)
Inverter
Emissions controls

And more per inspection
A/C refrigerant (look in the sight glass occastionally)
tires (you might expect this to be per mileage, but tires vary so much)
muffler and cats (you might expect per time, but they vary per weather)

 

[ElectricTroy]

if you start changing your oil after 30 or 40 hours of driving time, you will conserve your engine properly.

Yeah that's fine for normal driving, but what if I spend those 40 hours with the needle pegged on the redline? Then the "hours scale" is not accurate.




Anyway, either hours or miles... it's just meant to be a guideline. If you wanted an ideal measurement, probably engine revolutions would be best, but difficult to track without a gauge.

troy

 

[WayneBruce]

I'll say this about Rmarchena: he seems to hate miles. HPG instead of MPG, and hours per maintenance instead of miles.

Of course, this is nothing new. Any car manual always has both inspections based on time as well as mileage. That's why there's the "6 months checkup", vs. the 6000 mile tuneup. That's why warranties are "5 years or 50,000 miles." Whichever comes first.

Also: what ElectricTroy said.

 

[shaun944]

oil changes

"Instead, if you start changing your oil after 30 or 40 hours of driving time, you will conserve your engine properly. "

huh? even if you were going 60mph for all 40 hours, thats only 2400 miles

Your literally throwing away money if you change your oil every 2400 miles or less, unless you're running the cheapest dino derived sludge you can find. Not to mention the ICE isn't even running for all 2400 of those miles...

On synth oil only 2400 miles is ridiculous.

 

[jeromep]

This discussion reminds me of a sensor that GM is putting in some of their Buicks and other vehicles which actually uses some kind of resistance or other sensor criteria to tell you when your oil should be changed.

GM may not have the best vehicles in the world, but a sensor which tells you to change oil based upon oil condition, vs. time is a wonderful idea.

 

[DanMan32]

Is it a sensor that can actually check the oil condition directly, or a system that guesses the oil condition based on driving conditions?

 

[ElectricTroy]

This discussion reminds me of a sensor that GM is putting in some of their Buicks and other vehicles which actually uses some kind of resistance or other sensor criteria to tell you when your oil should be changed.

Actually, all it does is monitor the engine rpms and *estimate* when your oil needs a change.

Mercedes-Benz tried this, and they ended up with cars going 20,000 miles on non-synthetic oil, and many ruined engines.

troy

 

[jeromep]

Actually, all it does is monitor the engine rpms and *estimate* when your oil needs a change.

Mercedes-Benz tried this, and they ended up with cars going 20,000 miles on non-synthetic oil, and many ruined engines.

troy

I was under the impression that there was a sensor in the oil sump which actually used electrical resistance to determine the contamination level of the oil. Lots of vehicle parts manufacturers (like Delphi) have production oil contamination sensors out there. The last Buick I drove was a company car and it had the sensor and it seemed to offer reasonable oil change intervals as compared to interval we are used to.