I know this issue has been discussed to death. I performed a few searches and did find some useful information, but can't seem to find a definitive answer.

I have Toyo Proxes4 P235/45ZR17s mounted on stock 17s. The sidewall reads max pressure of 50psi. I just checked all 4 tires (cold) and they are all filled to 40-42 psi. That seemed really, really high to me, so I let them out to 33 psi.

Here's the question. What does "max pressure" mean? I know the term means that that's the maximum pressure you should fill the tires to (hot, I think), but in the real world, what does it really mean? Shouldn't all 16-17" tires be filed to around 32-35 psi, depending on driver preference? Isn't 40-50 psi way too high?

e-man

 

No, 40 is not too high, I run 40 on all my tires, and I have 17"s. The max psi on the sidewall of the tire is measured at the COLD, not hot.

 

i was running 48 psi on my 19s at one time...to tackle potholes....now i run it at 42 psi.

 

Hey e-your car probably feels a little plusher with 32-33 than 42 psi, huh? If you left them at 40, it would ride rougher,and turn in quicker but you probably won't hurt anything. I run about 32-34 for comfort. Right now I have my 18s at 34psi(still experimenting). My stock 16s, I ran at 33.

 

You're not kidding. The difference is unbelievable. I didn't notice an issue on the ride back from NJ because it was all highway. Over the last few days, however, I've sensed a bit of harshness. I assume I'll lose a little in the mpg and tire life departments, but it's worth it.

By the way, does this count as a mod?

e-man

 

Yea E-Man with are roads out here I was going to say Max for us should be 35-37 lbs

 

Keep in mind guys that the ride may be better at lower pressures but with potholes and bad roads you run a higher risk of damaging a wheel.

 

i currently run 40psi but now that pete has said he ran 48 i might just do 45psi now

 

I run at between 38 and 40 psi and havent had a problem. I think the max for lowpro tires is 50, so 48 is a little too high for me

 

with just 17s on the car, i would keep it around 35psi at most. there is no reason for you to run that high of a pressure. you don't have profile problem

 

Maximum pressure is a warning to those people who, for their own reasons, like to inflate their tires over the car manufacturer's recommended pressure. Reasons may include increased load carrying capacity, rim protection, personal preference, ignorance, etc. Those reasons (except ignorance, maybe) aren't necessarily wrong because the recommended pressure is just that: a recommendation.

JB

 

The question is simple and the annwer is simpler.

Max Tire Pressure: Is the tire pressure beyond which the tire may explode or gets deformed. Any user at what ever temprature (yes the temp chages the pressure) should not go above the stated pressure. Will the tire blow just .05psi over the stated limit, most probably not, but I would not like to be around to test it. This number comes from the tire manufacturer.

Reccomended tire pressure: Look on the decal (driver side door jamb). This is where the car manufacturer reccomends a tire pressure that gives the optimum ride-comfort handling, braking, fuel-economy, tire-wear etc. [patch of rubber in contact with the road]. Can you set your tire pressure above or below the 'reccomended pressure'. Sure, but you will move out of the optimimum point ... may be increased fuel economy, but poorer ride and lesser tire life. All factors do not move the same way, so something improves while another thig gets worse. But under no circumstances go near the Max Tire Pressure.

Salim

 

Well...that only applies if you still running your stockers.

 

I've been running at 40psi on my 18's in summer and run 38 on my 17's for winter