tire pressure

[Ping]

The tire pressure varies to what each person wants.  I have grown up servicing cars all my life.  Myself, I keep 32 pounds of air in my tires.  Each customer had their own idea of what was best for them and the way they drove their cars.  I am still using the old bias tires 600X16 on my Plymouth and have had very good luck with keeping them at 32 pounds.  They may ride a little harder, but the tire wear has always been my concern. As another fellow said, they seem to wear even and I get good wear out of them.            Ping

[Wm Steed]

OK.... here I go again

Tire pressure is like the difference of opinion that surrounds the use of thermostats, anti-freeze/coolant, multi viscosity oil, blondes, brunettes, red heads, little ones and big ones.  :o

Two factors come into play with the tire issue..... the desire of the vehicle manufacturer to make his vehicle ride nice and the desire of the tire manufacturer to make his tire preform well...... to this end you can't let the DIRECTIONS ON THE CAN OUTSMART YOU...
As a general rule the vehicle owners manual or a sticker on the glove box door or door jamb will state a certain pressure, usually on the low side to make the vehicle ride well, however, some place on this tire pressure sticker, or in the owners manual there will be wording that will state a higher pressure for heavier loads or hiway driving..

The tire manufacturer will usually call for a pressure at least 4lb's higher than the vehicle manufacturer.. The higher pressure will minimize shoulder scuffing and early tire failure from under inflation.  As a general rule, modern tires will have the recommended pressure stamped right onto the side wall.

Radial tires are a whole different bag of worms.. People are of the general opinion that radials are low pressure tires, they are in fact high pressure tires. If you look at the majority of vehicles with radial tires you will note that the shoulders of the tires are generally always scuffed off. This scuffing is a result of under inflation causing the tire to roll under on turns and/or 'cup' on the road with only the shoulder coming in contact with the road. 

On cars I have found it best to inflate radial tires about 3/5 lbs higher than the recommended pressure. I very seldom have a tire wear problem with the tires on my cars.

Several years ago Ford had a big problem with tire failures on vehicles with Firestone tires.... The actual problem was caused by two things.... Ford told Firestone to build a tire that did not meet DOT spec's...Firestone built the tire... if you look on any of these tires you will not see a DOT spec number. When the tires started to fail, Ford sent out letters informing the owners of vehicles with the tires to DECREASE THE TIRE PRESSURE. The lower pressure caused the tires to overheat, thereby failing....Bill 

[TodFitch]

Can someone tell me what pressure to keep in the tires of my 48 Plymouth? Is it 32 ppi? I only take it out for a drive on Sundays. Thanks, Mike ???

The 1946-54 factory service manual has the following cold tire pressures:

6.00x16 - 28 pounds
6.40x15 - 24 pounds
6.70x15 - 24 pounds

I assume that the pressure for Sundays is the same as for the rest of the week. :)

[57plymouth]

I keep my radials at 35.  I don't know about bias ply tires.

[48 Beauty]

Can someone tell me what pressure to keep in the tires of my 48 Plymouth? Is it 32 ppi? I only take it out for a drive on Sundays. Thanks, Mike ???