Recommended Tire Pressure

NICE.

I can see one of those in my future! Two summers ago I managed to blow up an old bike tire when I couldn't get the nozzle off or the compressor shut down fast enough.

 

I started running higher pressures in my G2 Prius to solve unequal wear patterns on the tyres. So at least my anecdotal experience is exactly the opposite of your concern.


OP:
Good roads ? Run as close to sidewall max pressures as you like the ride

Bad roads, Potholes ? Run at or close to Toyota Recc.

 

Speaking of...

I just topped off my tyres with a Bell bicycle pump a few minutes ago. Worked like a charm. Being fairly stupid sometimes, I had never thought of trying it before.

 

There is a huge volume of conflicting opinion on this subject. Living in a climate were true road ice is very uncommon compared to standing water and various forms of loose and compacted snow, I have been unable to separate the truth from the flood of mythology and speculation.

The Firestone - Ford Explorer issue was more complex. The tires were defective, manufactured without some of components specified in their design. The vehicle had several design problems, including specifying inadequate tires. And the drivers were abusing the products, speeding in overloaded vehicles at high ambient temperatures while not maintaining even the listed (and now known to be too low) tire pressure. And I'm probably forgetting some other factors.

 

I think it's pretty straightforward really.

What gets better traction, a woman's stiletto or a man's work boot?

What gets better traction, a bike tire or a massive dump truck tire?

It's pretty simple physics, more area equals more friction.

So I guess I shouldn't have asked the question because it's very obvious to me.

 

Einstein had some good advice on simple.

"Make everything as simple as possible, but not simpler."
-- Albert Einstein

 

Always best to understand physics before you start theorizing. In the simplest terms, friction is dependent on the product of the area and the force normal to the surfaces. So a woman's stiletto heel could actually provide more grip than a man's work boot if the weight on the stiletto were greater. Surfaces also matter: if the woman is standing on concrete and the man is standing on ice....... (this is called the coefficient of friction).
You're also apparently assuming that lower tire pressure will give you a larger contact patch. As pointed out in the Wiki article, this probably is not true for modern tires.
I think what fuzzy1 is saying is that if you are driving on ice, especially glare ice, tire pressures are largely irrelevant, you need studded tires or chains. On snow, the situation depends more on the rubber compound and tread pattern. In rain, again probably tread pattern matters a lot in terms of draining water away so the rubber rests on the road rather than on water.

In a complex situation like this, analogy and intuition can lead you astray. Einstein had it right.

 

Wow, a complete miss. Like I said, there is plenty of mythology out there.

Simplified classical physics says that area doesn't matter, the 'traction' is simply the coefficient of friction times the contact force. The real world of not so simple, but I don't sufficiently understand the more advanced treatments of the issue. You don't even understand the simplified classical version.

 

for our purposes here the coefficient of friction (ice and tire) and force applied (weight of vehicle) are the same therefore our only variable is contact area. I understand on a smooth road the surface area of the tire isn't changing much regardless of pressure but this changes quite a bit on uneven roads.

Go to any good off-roading website. They will tell you to decrease the pressure of your tires.

 

Sorry, I fanned out on that one too!!!

 

You guys are right about contact area not mattering. I made a mistake when I said that. Sorry for the mess up. But just based on anecdotal evidence I would still take my tires a little lower pressure in the snow/ice.

 

DITTO

I tried all combinations of pressures, ended back at factory recommendation as well.

 

I drive a gen 2, but like Josh2008, mine probably shouldn't be mentioned either 8)

 

now I have to hear both of yours

 

Lol! ..... I run 65 psi

 

Wow, just curious why 65?

Why not 55? or 75?

 

I was in the 50s at one time, just kept creeping up ...75 would be too harsh, afraid of breaking stuff haha....I have a stiffening plate, sway bars, trd springs & struts, etc, so 65 atm

 

Woah. I hope you never run into a pothole or over an obstruction.

 

I hope you mean 65 psi, not 65 atmospheres.

 

Sounds like you've researched this. Is 65 more of the "true max" of the tire?