Availability of 12 Inch Tires and Wheels For a Dual Axle Travel Trailer

Published 08/08/2011

Question:

I am replacing 4 plus spare tires on a little dual axle travel trailer. The specs for the trailer and what everybody else seems to be using is 5.30-12 6-ply tires. Im assuming a D rated tire would be even higher highway rated? Is that correct? But Im not sure whether the rims are 4 or 4.25 as noted in this listing. All the other 5.30-12 6-ply C tires are listed at 4. So Im guessing I have 4 rims. How is the rim measured? And will these tires then not fit my rims? If I bought these tires with rims could I assume the rims will fit my 4 bolt wheels?

asked by: Art l

Expert Reply:

A 5.30-12 size tire with a 6-ply rating (load range C) has a maximum load capacity of 1,045 lbs at 80 psi. So four of those tires on your travel trailer will have a combined load capacity of 4,180 lbs. If you go to a 8-ply rated tire ( load range D) in the 5.30-12 size the maximum load capacity is 1,250 lbs at 105 psi. Four of the 8-ply rated tires would have a combined load capacity of 5,000 lbs. This does not mean you can carry more weight, because you will still be limited by other parts in your trailer suspension, like the axle or leaf springs.

Most of the 12 inch wheels will be 4 inches wide, which will accept all three of the 12 inch size tires, 145/80-12, 4.80-12, and 530-12. These tire sizes will also work on a 4-1/4 inch wide wheel. A wheel is measured across the width of the wheel from bead seat to bead seat, not from the edge to the other edge. I am including a picture of where a wheel is measured for width.

The 12 inch wheels will be available in a 4 on 4 inch bolt pattern and a 5 on 4-1/2 inch bolt pattern. If you have a 4 bolt pattern in a 12 inch wheel, it will be a 4 on 4 inch bolt pattern. So, if you buy 12 inch tires and 4-bolt pattern it will fit your trailer with a 4-bolt pattern. I am including a link that will show you how to measure your bolt pattern.

When choosing wheels and tires for your trailer you will always want to make sure that you will have enough load carrying capacity for your trailer and that you run the maximum air pressure that is stamped on the sidewall of the tire.

expert reply by: Jeff D