How much Pressure in your 18" Tires?

[Nikolay_Ruskov]

How much tire pressure should I run on 225/40/18?
'

 

[Carlz0r]

How much tire pressure should I run on 225/40/18?
'

Your tires should say on them the pressure to run, and if they're like mine it'll be in the range of 35-40psi. That's the exact size tire I currently have on my wheels.

 

[Nikolay_Ruskov]

they are venezia..
Size 22540R18 Size Clean 2254018
Static Load 0.0 Tread Depth (In 32nds)
Overall Diameter 25.039 Ply Rating XL
Rim Width 8.00 Section Width 9.134
Service Desc 92 Tire Sidewall BW
Type Speed Rating W
UTQG 420 AA Mileage
Max PSI Single 49 Max Load Single 1389
Max PSI Dual Max Load Dual
Wheel Size 18.0 Weight 9.9790

that's all the info..Its tell me only whats the max

 

[ed1380]

I usually go 4 psi under max . Under 2 in the winter

 

[Nikolay_Ruskov]

ok ..thanks ..they are set on 35psi right now..but the traction own me..i have to go awd soon']]

 

[jtmcinder]

Your tires should say on them the pressure to run....

Nope. The tires don't know how much the car weighs. The tires only have a maximum pressure on them.

 

[JusMX141]

Always run near what the tire manufacturer says is the max pressure. If it says 44psi, run around 40psi...if it says 50psi, run around 45psi.

Our cars recommend something ridiculous like 32psi front and 29psi rear- the only time my pressure is that low is in the wintertime when I need more sidewall bite. The car manufacturer has no idea what brand of tires you're running, what ply the sidewalls are, or how large your rims are....there's no way they can recommend a blanket tire pressure suitable for all brands and types of tires.

 

[jtmcinder]

Not only do all cars have a standard, regardless-of-tire-brand, suggested pressure (see sticker in driver's-side door-jamb), but ever since the TREAD Act all US cars have been required to have some sort of tire-pressure monitoring that is based on the manufacturer's suggested pressure.

Yes, what pressure produces optimal performance can vary a bit from brand to brand. But since almost every aspect of performance (other than gas mileage) drops off when you over-inflate, the idea that you should base your pressure on the tire's rated maximum is getting close to being dangerous advice.

 

[and1chewy]

depends on what your trying to get outta the tire. if your looking for gas mileage you run a higher psi in your tire as your tires will have less drag. if your looking for comfort you go less psi. i like the 40 psi range for your 44 max as youll get a little of both worlds. comfort and mileage/performance.

 

[Bouche Dag]

You should always run what you're comfortable with - but never over the max tire press. or under about 5 lbs of the manufacturer specs.

I do 35 all around in my DSM running Michelin Pilot HXMX M4s (that are soon to be replaced with Continental Extreme Contact DWs)

 

[dudeX]

This is my first post, yea!!! : ) Anyways, I'm pretty sure running tires near max pressure is not a good idea. Part of the reason for a max pressure is to create a safety margin for things like tire heating and emergency stopping which both increase the pressure in the tire. That's why you're supposed to check the tire pressure when cold to allow for this expansion. What the manufacturers have done is found the correct psi for the tire sizes they run on specific vehicles that provide the fullest most consistent contact patch. When you go with different sizes it pretty much up to you to experiment and find this happy medium for yourself as the original psi most likely is not applicable anymore. I looked around for a tire size/ vehicle weight calculator online but couldn't find anything. Hope this was kinda helpful at least!

 

[PieEyedPiper]

I would also suggest starting with the car's recommended pressures and tweak it a bit from there instead of running your tires up to near max pressure.
http://cars.cartalk.com/content/advice/tirepressure.html
http://www.turnfast.com/tech_handling/handling_pressure <--- lots of info in here, still reading it

There are few situations where I'd run high 30's to 40+ psi, let alone 50.