changed rims... Tire pressure ??

[xoxo_tw]

Hi ! I have a 2010 Aveo hatchback, I put on some 17" alloy rims, with 195/40/R17 tires... what tire pressure is suggested to use ??

[uk stomper]

i would think around 32 psi all round

[northguest47]

here's some tests i did with my aveo, here's what i found:

44 psi in summer
35 psi in winter
27 psi on logging roads
----------------------------
buy a small pen style psi meter, put it in your glove box
money well spent, use the same gauge always

[uk stomper]

44 psi seem very high for summer driving

[xoxo_tw]

thanks ! I will try them..

[northguest47]

44 psi seem very high for summer driving

Yes I guess so, its the max I've seen written on the tires.. at 44psi the car just seemed to handle the curves better but you do lose some comfort. My friends Dad who is a mileage geek tried a whole tank cruising at 35psi and at 44psi. He did find that the mileage went down slightly at the higher pressure by a bit, so went back to 35psi. And definitely if you are driving on a long section of dirt and/or gravel road, try lowering at least the fronts for a bit to see how better the car feels.

[uk stomper]

not sure on what your weather is like over there but i would not dream of running my tyres at that 44 psi,
the heat in tho wheels will be very high

[MetroMPG]

Lower air pressure actually generates MORE heat in the tire (greater deformation in the sidewall).

Also northguest: your buddy's dad's mileage must have dropped for some other reason. Higher tire pressure means lower rolling resistance, which means better MPG (up to a point). It's really hard to test changes from tank to tank comparisons due to changes in weather, traffic, driving route, driving style, speed, proportion of city/hwy etc, etc, etc. He probably had done some searching and saw tests and studies that show better MPG at higher pressure. And... they are correct!