Tire Pressure
 

Hello.

My car says 38 on the door for the recommended tire pressure.. However I recently put new rims/tires on car.

Went from 17" to 20"
9" in front 10.5" in rear

245/35 and 285/30

Everything rode fine. I did not realize that place that installed them only put around 32 for pressure. When I just got oil just last night, they checked the door without me knowing and put 38 in the tires.. Things still seem to ride smooth and handle well.

i would just like to know if this is an issue.. Should i leave it the recommended?
My main concerns are Safety, and the looks of the tire and the way the car sits.. Things seem to look the same. but I can't be 100% certain yet.. not sure how much of a difference 6 can make.. Thanks.

You should be fine. I have been running 43 psi (245/30/20) and 45 psi (275/30/20) for about two years now. I don't feel safe when they are any lower or softer.

What purpose is it to keep low pressure in there? Why would people choose to do it then?
Does sidewall look any differnet? Or is it possibly a comfort or handling issue?

Thanks for the reply btw.

My car is a daily driver. I don't often drive above 90 MPH. If my psi are any lower, I feel like either the rims or the road will eventually shred my tires up. Besides, they seem to roll better (less work/friction) at my current pressures.

Tire pressure is set to maximize the tire's footprint and wear based on the weight of the car and the desired handling characteristics/balance.

So can you think of why the car place chose to put 32 in mine? They arent just a garage.. Theyre a pimp my ride type place.. So I was just wondering what their reasoning wouldu be.. seeing how the 38 is seeming like the right thing to do.

unless they were trying to help prevent it from rubbing. but i still dont rub with 38

Always go by what is recommended by the manufacturer. When we install wheels/tires, we ALWAYS inflate to the PSI on the door. Under inflating is going to cause premature wear.

Actually, the manufacturer (BMW) does recommend 32 psi for the OP new tire size and 38 for the 225 size. So 32 is good.

salut, Bob p.

most manufacturers say 7-10 under max for "most" driving conditions. as that will give you the best ride and handling for the average person. now load up trunk put a person out back and doing 800 miles i tend to run closer to max. they count on you doing that cold so they know when you warm up tires the PSI comes up. the more air in it when it's cold the harder the tire rides