Which Tire pressure do I go by?

[Dylansav]

I went to the mechanics yesterday to get an oil change/lube and underbody inspection. They also checked my tires..They found out one ting with them...

I was going by what the tire store told me to fill them up at (about 40 psi) and the mechanics said that I should always go by the truck's spec of around 30 psi. They deflated the tires to around 34 psi now and just notice that I hear the tires more when driving down the highway. Who should I trust?

Also...there was one thing else I noticed while driving home lastnight. I heard a SQUEAKING in the rear left tire that disappeared after going over 30mph but was pretty loud under it. any ideas of what that was? I was so scared...


Thanks for any help again guys

 

[JDraper]

Your tires should be inflated to what the truck states in the manual or on the door frame.

Squeaking could be any number of things. It could be as simple piece of gravel stuck between the rotor and the dust shield to brakes rubbing a little to a bearing issue. It's almost impossible to accurately diagnose it without hearing it.

 

[Dylansav]

thanks JDraper, I really think that squeaking was something stuck in the rotor like you said. I can't reproduce the squeak but it did kind of sound worn pads on rotors squeak. I dunno if that helps at all hehe... But the squeak is gone now and I haven't heard it since.

So always go by what the truck says and not what the tires say right?

 

[JDraper]

What is on the tires is the MAXIMUM safe cold pressure for the tire, independent of the vehicle. The vehicle weight, cargo capacity and design determine the correct tire pressure for any given tire, and that is what is listed on the vehicle. The listing on the vehicle may not be perfect for every driver or load, but is the best compromise for the vehicle. If you carry a heavy load, you would want to up the pressure in the tires. If you're driving off-road, you would decrease the pressure to increase the contact patch area.

For general driving, go by the vehicle specs.

 

[Dylansav]

oooh god that's not good than if I go by the tire

YOU may have saved me a few hundred bucks in tire replacement! (not to mention injury!!)

I owe you

 

[BigODave]

I second what JDraper has said here!