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Papa_Jim · 02-13-2011, 10:45 PM

Need some help here.

I have a tire that's rated to carry 6,175 lb. @ 110 lb. inflation pressure. It also states that's for a maximum speed of 75 MPH.

So, if that tire is carrying 5,000 lb, at 60 MPH, what should it's inflation pressure be?

I know, 110 lb. to be safe. But, is there a formula so that the tire can be inflated to the proper pressure for safety, and also provide the smoothest ride?

I thought there should be a chart for this kind of info, but so far I haven't been able to find one.

Fred Cooper · 02-13-2011, 11:30 PM

Most tire manufacturers publish tire load & pressure tables. You didn't state tire size/brand.

I found an example, but can't get the link to work. Google "michelin truck tire data book" and you'll find several links. Download one of them (pdf file) then look on page 14 for 22.5 size.

It may take a bit of searching via google, but you should be able to locate a table for your tires.

Do you have actual wheel weights for your coach instead of axle weights? Many coaches are heavier on one side.

Good luck.

Fred

InPursuit · 02-13-2011, 11:57 PM

Quote:

Originally Posted by jimkate

Need some help here.

I have a tire that's rated to carry 6,175 lb. @ 110 lb. inflation pressure. It also states that's for a maximum speed of 75 MPH.

So, if that tire is carrying 5,000 lb, at 60 MPH, what should it's inflation pressure be?

6175 lbs vs 110 psi = X (up to 75mph)
5000 lbs vs Y psi = X (up to 75mph)

Solve for X

Dacotah · 02-14-2011, 07:24 AM

Jim, from what I understand it is a factor of what weight is carried on that tire or set of tires. The 75MPH is the maximum speed the tire is designed to be run at. Every truck or RV tire made has a load chart for it that states weight carried VS tire pressure. The problem is if you do not know the weight carried at each point including full fuel, water, cargo and passengers, you will not be able to use the chart. Hope this helps. DACOTAH

Papa_Jim · 02-14-2011, 11:11 AM

Thanks for all the replies. The lead to the Michelin tire pressure chart was the right one, it provided the answer I was looking for.

http://www.michelintruck.com/assets/...k_Databook.pdf