Tires: tire noise, proper inflation pressure, truck mileage


Question
I have good radial tires and faily new on my '86 toyota pickup... I have started to hear this light slapping sound from outside the truck. It sounds like its coming from the left front.
tire pressure is 30 psi.  what could be the problem? truck mileage is 140,000.
thanks for your help,
john

Answer
John,

This is probably irregular wear, which is caused by misalignment and aggravated by low inflation pressures and prevented by regular rotation.

First you need to find the placard:

The placard, among many things, tells the original tire size, the original wheel size, and the proper inflation pressure for that tire size.  The placard is usually located on a doorpost or in the glove box.

I like to use 3 to 5 psi above the placard.  I get better fuel economy, better tire wear, better wet traction, better snow traction, better steering response, better tire durability, and only give up a bit of ride harshness.

"They" say you should check your tire pressures once a month.  (In case you didn't know, tires leak very slowly.)  Don't trust the guys at the shop to check your inflation.  These guys are paid by the hour and this is one of the easiest things to shortcut.  Besides, there are a lot of mechanics you don't know where to look for the proper inflation.  No, it is not on the sidewall.

Second, you need to be rotating your tires regularly.  Most vehicle manufacturers recommend 5,000 to 8,000 miles.

Third, you need to get an alignment.  Look at the tires.  Are they worn evenly? Rub your hand over the surface.  There will be some natural wear pattern, but it should be the same from tread element to tread element.

BUT, just in case it is something else, have your tires looked at by a professional.

Hope this helps.