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Old 06-19-2017, 09:25 AM   #8
Bill
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Location: The mountains of Scottsdale, AZ, and the beaches of Maine
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Quote:
Originally Posted by Meteor View Post
I have a 2008 2720 for which I need to buy new tires. I'm trying to decide whether or not to buy 14" tires as it currently has, or go ahead and move up to 15" tires now rather than later. But how do I know what tires will fit?
You asked several questions, of course, and the answers have changed over the years.

TM owners used to upgrade from the OEM 14-inch tires to 15-inch tires in order to get more load capacity. At that time, all 14-inch trailer tires seemed to be Load Range C (about 1850 pounds per tire when inflated to the max pressure of 50 psi). If you wanted increased load capacity, you had to go to a 15-inch tire in order to get to Load Range D (about 2250 pounds at max pressure 65 psi). That is no longer true. If you look around, you can find 14-inch tires in Load Range D, so the upgrade is simple - just buy new 14-inch Load Range D tires, install them on the old 14-inch wheels, and you are good to go. (Caveat - make sure the old wheels are rated to hold 65 psi.)

So if you do your homework, the question of 14-inch vs 15-inch is no longer a question of load capacity.

If you change from a 14-inch tire to a 15-inch tire, it will give you a small increase in road clearance - about 1/2 inch. Not much, but you have to decide if it is important to you.

As for the fit of a 15-inch tire, TMs seem to have plenty of clearance behind and ahead of the tire. They also have enough clearance to the left and right of the tire. The remaining question is whether there is enough clearance above the tire - you don't want the tire to rub on the plastic wheel well liner above it. Dexter Axle, the supplier of TM axles, says that there should be 3 inches of clearance above the tire when the TM is loaded for travel. Since 2 inches appears to be more than adequate, I asked Dexter why they suggest 3 inches. They were unable to explain it, so several of us (including me) run with a bit over 2 inches of clearance without problem.

If you want to move to 15-inch tires, and you have less than 3 inches of clearance, and you are nervous about that, then the easiest solution is to install a lift kit. In addition to increasing tire clearance, a 2-inch lift kit will increase road clearance by 2 inches, which is a worthwhile amount if you intend to go rough-road or off-road at all. Some folks worry about raising the center of gravity of the trailer, but I don't think that an extra inch-and-a-half has any noticeable effect. However, remember that since it lifts the TM body, a lift kit reduces the clearance under your garage door.

Everything is a trade-off, isn't it? But my guess (you should confirm it) is that a 2008 has plenty of above-tire clearance. If you want to move to 15-inch tires, you can do so without installing a lift, and without affecting your garage door clearance.

Bill

Quote:
Originally Posted by Meteor View Post
I can't seem to find the answer in the existing posts.
This thread belongs in the Tires area of the forum, and I will move it there in a day or two. But that explains why you couldn't find the answers - since you are not a Site Sponsor, you can't see that part of the forum.
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