Wimp. I took the electrical leads coming in from the power company, connected one lead to both hots and replaced the neutral with the other lead, so everything is running 220. Now that's hypervolting.

 

from 32-36 you will not notice any FE difference. At least nothing worth mentioning.

 

I love it. No guts, no glory. And you should see what the vacuum does to the carpet!

 

Sucked the padding right out from under the carpet.

 

The effect of tires heating up is taken into account when deciding the pressures, which is exactly why they are specificed as cold pressure. When the manuals however suggest a +5 PSI boost for higher speed driving however, this means a +5 COLD boost.

What this suggests however is that there is a range of pressures where traction etc. are more or less the same, and that manufacturers normally opt toward the lower end of this spectrum in order to create a softer ride, at the expense of greater rolling resistance. I know that one of the main contributing factors to the ford/firestone blowouts was that Ford specififed an unusually low spec. pressure in order to produce a softer ride.

 

Just as an FYI....From ToyotaiGuide:

When driving under the above vehicle conditions (Tire size and cold tire inflation pressure) at sustained high speeds above 160 km/h (100 mph), in countries where such speeds are permitted by law, inflate the front and rear tires to 240 kPa (2.4 kgf/cm 2 or bar, 35 psi) provided that it does not exceed the maximum cold tire inflation pressure molded on the tire sidewall.

So they say only a 3 PSI increase for high speed... and much higher than we can drive legaly in the US. FWIW, I just put mine at 37 cold....we'll see if i get any improvement in FE, but my belief is that low pressures (under 30) will hurt FE, and tire wear. Over 40 MIGHT help, but I am not willing to go that high...mostly due to MY percption that it reduces the contact patch, and increases impact harshness more than I prefer.

 

I know that one of the main contributing factors to the ford/firestone blowouts was that Ford specififed an unusually low spec. pressure in order to produce a softer ride.

I have driven several explorers and am currently in a 2001 for a company vehicle. I looked into this a lot! It's extreemly easy to allow tires to go to underinflation. That will cause blowouts. However with the Explorer, Firestone and Ford finally agreed on 30-32 MAX. That was a compromise as one of them (I can't remember which) wanted it lower. The EXPLORER has absolutely "twichy" handling with pressures over 34 psig. I would call it dangerous for any interstate speed driving. Every time I take it in for service at a non-Ford service they pump up the tires to 36 and I have to let it out.

I will say that I owwned 3 Explorers in the 90's and traded my last one because of the stiff ride. This particular 2001 has an extreemly stiff "unforgiving" suspension and with high tire pressures does not like sudden moves (or corrective actions). I

Running at lower pressures means I have to check tires more often because losing 3-4# means I am then underinflated. VERY small margin of safety.

Breing as the TCH is a car and less prone to roll-overs, this particular aspect of high pressure tires does not concern me.

 

I know the manufacturers went through some radical changes for the sake of increasing FE across their fleet for EPA averages. If they were willing to change the grade of oil across their fleet for a 0.1mpg corporate increase then why would they have not increased the air pressures in the tires for the same reason? I'm sure they studied it under classroom conditions. I just can't imagine them not wanting a 10% increase if air is all it cost them.

I know, comfort you say. I don't believe they would have let that stop them, especially knowing that the consumer would simply let some air out of the tires as they wouldyhave a larger "range of safety" posted on your door post had they done that.

I can't see any difference in 32 to 36 psig and I'm not going above that.