Tire Pressure Oddity

[gizmopt2002]

So the weather in Chicagoland is around zero to -10. And it just snowed and i noticed that the tires have little grip unlike before. So I look and the tires are all at 27.5. So I fill them all up to exactly 40. I go out for awhile, the grip has improved, or at least so I think. Then after I get home I check all of them again to make sure they stay that way. I check them and they are at 38. So how did I lose 2 PSI in all of the tires in matter of 5 hours? This has me wondering. Any input?

 

[Toyboomer]

tire pressure

Because it affected all four tires it is probably not the tire. That leaves a temp. or altitude change. It is probably not altitude change where you are. For every 10 degrees warmer/colder a tire will change .5 to 1.0 lb. psi. Was it possible you aired up the tires in a warmer place? For every 1,000 ft. up/dn in elevation a tire will change approx. .5 psi.

 

[gizmopt2002]

Yea actually
I did air up the tires in my garage which was 22ish and it was about -1 outside.

 

[Toyboomer]

air pressure

That could do it. I live in the CO mtns. and often check my tires in the garage before I go on a trip. I have to be careful about what my average air temp and altitude might be where I'm headed. With a little Kentucky windage I usally come out ok.

 

[gizmopt2002]

Mmk. Well Your suggestions were indeed right. Now I have another question. What do you REVO people inflate your tires at?

 

[Toyboomer]

psi

I inflate my Revos to around 35-36 psi here in snow country and believe the snow traction may be a little better than at 40 psi but I don't have much data to support that. 36 psi is above the door panel recommendation so it gives some handling and plants a good footprint for traction. I have never used 40 psi although some of the members seem to esp. when towing. Pressure below mfg. recommendation makes traction worse in snow/ice and too high does the same. You might look at Tire Rack and see what they recommend but my experience is that a pressure a little above the door panel figures gives the best combination of handling and traction.

 

[druuu88]

i run 35-36 psi as well.. works well in the snow and gets a litttttle better gas mileage than the toyota reccommended 29 psi