42.3 mpg to 48.5 mpg

amazing how that works, isn't it ... with all the setup basically
done and getting stuck in rush-hour stop-n-crawl this morning,
I pushed my avg from 52.something up to 55.x in subfreezing temps
on about 3/4 of a tank left. There's a lot to be said for setting
up favorable initial conditions and then playing them for all
it's worth.
.
_H*

 

omgitsroy326,

Which dealer delivered your new 2008 Prius to you so severely underinflated? Don't they even look at the door post chart that says 35/33? I'm NOT saying for YOU to use 35/33 (because I too use 42/40), but the least pressure you should expect to see from the dealer is 35/33. Sounds like they need to specify in large print or bold face in the Toyota Prius prep document to "inflate front/rear tires to a minimum of 35/33".

After my 5K, 10K, & 15K service visits I got the car back with 32 PSI all around, 30 PSI all around, & either 24 or 28 PSI all around. Somewhere in between each 5,000 mile interval when I checked my pressures that is what I found, so I would pump them up to 35/33, but by 15,000 miles the damage was already done. All my tires were worn evenly (on both inside & outside edges) to the point there was no noticeable tread on those outside edges, but beautiful deep tread in the center of all the tires.

Since then I've insisted on & verified immediately the same 42/40 that you're now using. One of the times they even told me that they could not legally do that because the tires wouldn't take that kind of pressure until I showed them the 44 PSI max rating on the sidewall. I'm now at 49,3XX miles & have not noticed any more wear on those outside edges, but the wear on the middle is now finally catch'g up. I imagine I will get to 55,000 by the time I need new tires. By the way, they're the original Goodyear Integrities. Some Prius owners have had to replace their original tires between 15,000 & 20,000 miles (probably due to the wear from the severe underinflation like you & I have had).

By the way, one tire shop I visited (to get some prices on what I may buy) showed me the tire pressure settings for the Prius on their computer database, & said they would not exceed the 35/33 even with a higher PSI max rating. So it just looks like I'll have to bump them up to 42/40 myself after I get out of their shop.

Ken (in Bolton,Ct)

 

I am now running 44/44PSI front and back on my 2007 with the original goodyears, and am getting 48+ on my frequent SAN-PHX trips. That trip covers 750mi, including a significant climb above 4000ft thru the Laguna mtns each way. When I ran 35PSI on the same trip, I averaged around 45mpg. My speed is always at the limit: 70mph in CA, and 75mph in AZ. So, added tire pressure results in significantly better mileage. BTW, I don't notice any problems with harsher ride/handling problems with these tire pressures.
During one trip, I followed a large semi (closely, in the draft) for about 60 miles @ a steady 70mph, and averaged 59mpg during that stretch. My wife was a little nervous tho', so I don't do that anymore.

I'm 70yr young, have owned over 20 different cars during the last 55yr; This is simply the BEST automobile I have ever driven, bar none.

 

Great mpg! I am noticing the same thing on my Prius as well. For the first 2K miles, I am averaging 43 to 45 mpg. After my first oil change at 2.5K, my mpg consistently stays around 48 mpg and at times I reach 51 mpg.

If this great mpg continues, I will be tempted to take my car out to dinner on Valentine's day.

 

My dealer delivered my 07 with 28 lbs all around. Frankly I don't think any dealer gives a sh*t about tire pressure.There to busy leaving grease stains all over the interior. I wouldn't even bother mentioning it to them as you will have to check it anyway much less making a big deal out of it and arguing with them about it. Cause even at 28 lbs when you look at the Integritys they look fine. But there's about 5 mpg's of gold found between 28 lbs & 44 lbs of pressure. I run 43-40.
If your waiting to check tire pressure on this crappy tire every 5K your wasting your time. I now check pressure about every 5 days especially if there's been a cold spell warm spell. I bought a $ 19.99 tire inflater from Sears that plugs into the cig lighter recommended here that works great.I keep it on the back floor and use it often.

 

I took a nail in one of the GY Integritys that was not repairable at 15,000 miles. So I bought a pair of Michelins for the rear and I'm going to run the GY on the front without rotation until I wear them off, then get another set of Michelins for the front and go back to regular rotations.

Anyway, I run 40 / 38 and I reset the TPMS for those pressures. When I got the car back with the new rear tires, the TPMS warning light was on. I drove a couple of miles back to work (where we have a compressor) and checked the rear tires. 32 psi. Brought them back to 38, but the warning light is still on. Checked the front, 32 psi. And this is from a tire store.

So my TPMS is really a DMWMTS (Don't Mess With My Tires system).

 

Nope, even though I had synthetic oil at the 2nd maintenance. Right now I am avg 46 with the synthetic oil over 3000 miles.

It seems I can't get back up to 51 ever after I had the first service. Sure, I was paying a lot more attention to mpg while driving the first 5000 miles, but right after the 1st maintenance it dropped to avg 45.5. tyre pressure is probably the most effective measurement IMHO.
On long trips following trucks in some distance is also a good strategy to save gas, they're slowing down slowly going uphill and vice versa.

frosh

PS In Germany I drove a VW Lupo, a diesel at about 65 mpg

 

Well I had a different experience. My mpg shot up after putting in Mobil-1 synthetic at 3500 miles. I immediately noticed the change in my car.

I will say that mpg on the prius seems to be an incremental task. It is a combination of methods which render the improved mileage. I use grille-blocking, synthetic oil, route-planning, and pedal-control. I haven't had the patience yet to add an electric block heater, and I am unwilling to trade the softer ride of standard tire inflation for the wheel hop of high inflation.

Though this is my snapshot, there are many others. Different strokes for different folks.