I was tired of my wife getting 46 mpg and myself having to work hard for 50 mpg. I have over 30k on the OEM tires with a good bit of tread left, some corner rounding and was running 42/40. I decided to put 60 PSI all around to try to extend the tire life and increase the mpg. As far as safety, we are NEVER even half of the rated load capacity and we don't live in the tropics (less heat = less pressure, companies build and rate for the extremes) and I drive within the limits of the car I am in ( ever driven a 64' Plymouth?). Three tanks in: 53, 53 and 58 mpg half way through this tank. Car performance feels great, more responsive. No problems in the rain either. I have gotten a 5 mpg boost. Please report your high PSI results.
<div class='quotetop'>QUOTE(etyler88 @ Aug 29 2006, 09:23 AM) [snapback]311057[/snapback]</div> Isn't 60 PSI exceeding the limit on the tire? I run 38 front, and 35 rear, and get in the mid 50's. I tried higher pressures, but they seemed to make the ride harsher and cause more rattles over some of the rougher sections of road I drive. I'm on the stock Goodyears, around 16K miles.
<div class='quotetop'>QUOTE(Beryl Octet @ Aug 29 2006, 09:37 AM) [snapback]311063[/snapback]</div> I have also seen an increase in mileage at 56/54 vs. 42/40 but I have also tried a new technique (new for me anyway) called pulse and glide. I would go for 60/58 vs 60/60 but it may not really matter. My mileage has gone up by about 10 mpg vs last summer maybe half of this is tire pressure and the other half is technique. At highway speeds (where pulse and glide doesn't work) the increase in mpg was about 2 mpg (57 vs 55 at summer temps), my guess is that this is probably the increase around town as well from tire pressure. Try pulse and glide at speeds under 40 mph and your slow speed mpg can go way up, I have managed 50 mile round trips at speeds between 33 an 40 mph getting 94 mpg, others have done even better, I think as high as 118 mpg for over 1400 miles on a single tank! (This was a woman in Japan.) The best I have managed for a tank is just over 70 mpg. There is one person (see My Precious Prius at greenhybrid) who has been getting 83.x mpg from June 15 to Aug 17. Dennis
That's pretty amazing mileage. I've topped 60MPG on some trips, but most of my driving is in heavy enough traffic that I can't really pulse and glide (I'm new here, but I'd been lurking for a while). I do coast up to lights etc. as much as possible.
<div class='quotetop'>QUOTE(berylrb @ Aug 29 2006, 11:07 AM) [snapback]311108[/snapback]</div> how do you pronounce that? Like Barrel?
<div class='quotetop'>QUOTE(etyler88 @ Aug 29 2006, 11:18 AM) [snapback]311117[/snapback]</div> Like burle, as in burled walnut
<div class='quotetop'>QUOTE(Beryl Octet @ Aug 29 2006, 11:22 AM) [snapback]311120[/snapback]</div> As in squirrel on a whirl, or to hurl after leaving the gym because you did too many curls? I'm sorry, I'm bored.... :lol:
I hope you don't get the chance to tell everyone in the grave yard about your high mileage, but you are crazy to overinflate by so much. There are safety reasons why tires are set for max air pressure.
I run mine at 40/38 and may eventually try the 42/40 but I'm happy with the pressure they're at currently. I certainly wouldn't try to exceed the PC recommended pressure though.
Doesn't higher pressure reduce friction with the road, which increases breaking time, thereby increasing accident risk? I don't know this for sure, just guessing. I wonder if there is a liability issue here. Mine are at 42/40.
I just pumped 'em up from the OEM 35 psi all around to 38.5 - 36.5 and have realized about a 3-4 mpg increace half way through this tank of gas. I think this weekend (or next fill up) i'll go up the 42-40 and see what happens. just scares me alittle, never had passenger car tires that high.
I tried 42/40 and it was awful. Car skipped around on bumpy roads and the ride was rough and noisy; and the interior was much more prone to rattles. Didn't seem to make a huge amount of difference to mpg either.
<div class='quotetop'>QUOTE(Rancid13 @ Aug 31 2006, 07:19 PM) [snapback]312431[/snapback]</div> I just had my 5k service and had my tires set to 40/38 also. I'm really curious to see what effect it will have. I've been getting 56MPG over my 50-mile commute (80% on the highway).
<div class='quotetop'>QUOTE(mike_m @ Aug 31 2006, 05:00 PM) [snapback]312400[/snapback]</div> Sorry jumping in here a little late. My understanding is that "Beryl" is a woman's name in England and pronounced "barrel". But the German name "Berl or Burle" or other derivations is pronounced like "Squirrel". However, my mom who simply understood it as that semi-precious stone lining the heavenly city, gave me the woman's spelling and the German pronounciation. I'm a boy, LOL <div class='quotetop'>QUOTE(Rangerdavid @ Aug 31 2006, 07:03 PM) [snapback]312449[/snapback]</div> someone said on another post that the real increase is around 1-2% and that folks that see an increase of 5-10% are really just driving better, paying attention more since they (me included) are trying new things. A psychological boost, eh? Kind of like after a good workout at the gym, I leave and my posture is better, my attitude is like, "dude I know I'm bad, albeit overweight, balding, ... but I'm so pumped!" LOL
