Do Speed Ratings of Trailer Tires Vary Based on Tire Size

Question:

Is it safe to run 4.80-8 trailer tires at the same speeds of 4.80-12 tires on long distances?

asked by: Lawrence H

Helpful Expert Reply:

Trailer tires are generally rated for a maximum speed of 65 mph. This is true for both radial and bias ply types. The tire diameter does not have a direct relationship to its speed rating.

What is most important for any trailer tire is that it be inflated to its specified psi. The load rating for any tire is dependent upon it being inflated to its maximum rated psi. For example, if a tire were rated for a load of 1000 lbs at 90 psi and were inflated to only 80 psi, it would not retain its full load capacity. Running a tire in an under-inflated condition can lead to excessive heat build-up in the sidewall and may also lead to premature failure.

I have included a link to a helpful article on tires that may be useful to you.

expert reply by: Adam R