I am towing a 40' fifth wheel toy hauler. Should I stay with the standard 17" wheel for max capacity or change to something else. I would rather not go with a lift kit needed for larger wheels as it raises the bed height. Any suggestions?

 

The taller the tire (not wheel) you use, the lower your RPMs will be @ cruising.

Without your current size listed, it'll be tough to give you an estimate.

Assuming (from you saying 17") you have a Gen3 with 265*70*17s. That said, you can't downsize to a 16" due to the brakes. There is also the option for 245*70*17s that came on those trucks.

 

The smaller the rim the larger the tire sidewall (to stay with the same overall diameter) the more flex = more heat and wear. Changing sizes doesn't change the tires until you get to the 19.5's where you can get a dramatically better tire. The only sacrifice to 19.5's (other than the initial cost) is the ride quality. However due to the better tire the wear is considerably longer.

some 19.5's are "G" load rated which is up to 6175lbs per tire. An average 17" tire is only good for 3195lbs. So unless you go big there isn't any improvement in changing wheel size.

 

Also, the larger tire/wheel you go, the more rolling mass there is toward the outside of the radius, making your brakes work harder to stop you, or increasing your stopping distance. It's not overly dramatic tho unless you do a large change.

 

Great Info,

My current tires are the stock 235/80R17

So if I understand, going to 19.5 (as long as the overall height doesn't change too much) can have a higher load rating.

Do 19.5 wheels require any lift?

 

as long as your outer diameter remains the same, no.

 

Thanks for the help.

 

What is the pin weight on your trailer?