Will Increasing from 15 Inch Rims to 16 Inch Rims Help Prevent Tire Failure

Question:

8000 lbs boat with fuel and water on 4 axle. Road speed 70 MPH - 300 - 600 Mi. Load range E tires have constant failure. Considering a change to 16-inch wheels and tires. The space between the tires on each axle will be reduced to 2-inches. Other parameters are manageable. Is the spacing issue critical ? Owner Getting desperate and does not wish to drive slower. Suggestions / recommendations welcome. Thanks!

asked by: David W

Expert Reply:

Increasing the tire size will not necessarily keep your tires from failing. It depends on why they're failing. The biggest reason trailer tires fail is heat build up from things like exceeding their speed rating or weight capacity, or not inflating them properly. Trailer tires should always be inflated to their maximum psi with the tires cold.

The amount of space you have for clearance is important. You need to have 3 or 4 inches between the tire tread and underside of the fender to allow for the trailer to move on its suspension. You also want about 2 inches between the tire's sidewall and the inside of the wheel well. If the tire makes contact with the trailer you're just going to be having more tire issues than you already are.

Using 4 tires with an E load range should be enough weight capacity for a 8,000 pound trailer. I've linked our selection of load range E tires for 15 inch rims like Taskmaster # TR225LRE. The Taskmaster has a speed rating of 81 mph which is higher than many trailer tires. They're size 225/75 R15 tires.

I've also linked our selection of tire and wheel combos on 16 inch rims. They all have either a 6 on 5-1/2 or 8 on 6-1/2 bolt pattern so you may need to replace your hubs as well if you go this route. There are some that offer load range F and G so the capacities available are higher.

expert reply by: Charles S