Tried seemingly everything to increase MPG -- wondering if I need a new battery

While I haven’t collected a lot of “data” (a nod to bisco ), I have noticed a commonality to “I’m getting poor gas mileage” posts: a lot of those who have this complaint use the Prius as a camper. Wonder if that might be part of the problem? Just an observation.

 

Can’t imagine mpgs going up when burning gasoline with car in park.

 

[QUOTE


I'm not such as a moron that I'd include camping in my averages.

I'll be back after looking into the aforementioned stuff. Thanks again for the responses.[/QUOTE]

No one is calling you a moron, but you may be missing the point. Your Prius was designed for a specific purpose. Is it, even remotely, possible that using it for purposes that exceed that design, just might, maybe, be a cause of your problem? What happens to the vehicle on the weekend, actually can have an affect during the week (kind of like life in general).

 

The three things I did that improved my fuel economy were new wheel bearings @223K, ATF fluid change and a new Project Lithium Battery pack. I would recommend trying the first two before replacing the battery.

 

Curious, how does changing ATF boost mileage? Also, I'm assuming it's automatic transmission fluid?

 

Yes transmission fluid. Toyota says it is a lifetime fluid but what is lifetime? To toyota that is 100K. Not sure the exact science but from experience (I have changed it twice in 230k) the new fluid makes the whole transmission run smoother which increases efficiency and thus mpg. I used by amsoil ATF the first time and toyota ATF WS more recently and I haven’t had any issues. The amsoil performed great and I plan on buying more soon.

 

"Lifetime" for a manufacturer mean until the warrantly expires. Or epa warranty expires.
Which is 50,000 miles.

 

Check the rear pins also. They stick more than the front.

 

Took mine out of Power Mode after many years.

back to Regular Mode.

Hybrid battery running much cooler.

MPG is backup.

2013 with over 213k.

 

I never heard this one before.
What is the 'specific purpose' of a Prius? Is it in writing somewhere in the Owner's Manual?

I assume you think it has something to do with only driving on suburban streets and less than the speed limit on highways....

 

Have you looked at the rears? You can do a simple spin-test with the back wheels too; there’s a link in my signature on that.

 

Sorry boys i just skimmed this thread and may have missed it. OP did you clean and lube the brakes? it needs to really be done once a year for maximum mpg. clean and lube the slide pins with sil-glyde. do the clips witha high temp ceramic grease. don't lube the tips of the pins or bushings. you'll never get it in lol
As the brakes never wear out on hybrids if you drive correctly this is really all you need to do.

 

Somewhat dependent on yearly miles too? FWIW, both Toyota USA and Canada recommend a more in-depth "brake inspection" (with next to no explanation of what that entails) tri-yearly or 30K miles. Which seems reasonable, unless you're in hopeless salt belt conditions.

 

Honestly its still within a year. I guess since im not in the salt belt the heat down here adds to the lubricant evaporation. A year after doing my lubes you can pull the pins out to inspect and every time there is about the bare minimum of grease left and it takes xx lb-ft of torque to rotate the pins (a lot more than you can do by hand) and pull them out to look at. I know the caliper is stronger than I am, but yeah. 2-3 years+ is probably where you would start to see the big seizing stuff. The brakes will still work though don't get me wrong. Just waste a bit more energy and the caliper clamps unevenly the more they seize up.
Also, if the Zinc coating or whatever has worn off your guide pins always replace. If these pins get rusty they will weld themselves into the holes and you won't get them out sometimes.

 

I never did maintenance on the caliper pins except when changing pads. Of course for the Prius this happens once every 150-200k miles which is every10-15 years. It is too long.

Maybe I should add this maintenance item every couple of years. For example the almost maintenance free electric cars still have on their maintenance schedule caliper pins to be lubricated. So the Prius could benefit as the brake system is used in a similar way even if it was not on the maintenance schedule back then.

 

This is very true!
Every brake failure I have had over the the years was always because of a sticky (or totally rusted) caliper slider pin.
But then I live in Salt Country...
'Floating calipers' need to be free to move left and right. Without the pads in place you should be able to push and pull the caliper without too much resistance.
Fixed calipers which have pistons on both sides don't have this problem, but those are mainly used on Hi Po cars.

 

Reminds me of the Honda days. The mpg guys would swap their disk brakes to drum brakes for less drag.

 

Niether the disc or drum brakes should drag. If they do, it's a problem.