Tire diameter

[dcheatwood]

I'm going to repalce my original Trail Express tires at some point. They are 225 75R 15C. I want to go to D-range tires. The problem is that on my unit, I only have 2 3/4 inches of space between the tires now. The Rockwood 8282WS has torsion axels.
My current C-range tires are 26.5" diameter. I can't find D-range tires less than about 27.5" diameter. That would close the distance between the tires even more. I guess my question is this. How close can I mount my tires and still not worry about them touching while towing. I'm surprised that they came so close. Any input appreciated.

[ependydad]

I do NOT have torsion axles, but I can say that my tires are about an inch and a quarter apart from each other.

[AquaMan]

Where did you get your measurements from? By measuring or from the manufacturer? Most tires that size I'm finding are around 28.3". I would think as long as you put same size back on, you should be fine, regardless whether they are C or D rated.

[wmtire]

Originally Posted by dcheatwood

I'm going to repalce my original Trail Express tires at some point. They are 225 75R 15C. I want to go to D-range tires. The problem is that on my unit, I only have 2 3/4 inches of space between the tires now. The Rockwood 8282WS has torsion axels.
My current C-range tires are 26.5" diameter. I can't find D-range tires less than about 27.5" diameter. That would close the distance between the tires even more. I guess my question is this. How close can I mount my tires and still not worry about them touching while towing. I'm surprised that they came so close. Any input appreciated.

I'm not sure I understand your question here. Are you replacing the tires with the same size as your original tires?

If so, then Load Range/Ply Rating doesn't usually make any difference in the actual diameter.

Although there are some small diameter differences between tire brands/models, depending on how they measure the tire....it's usually fairly small.

What can affect the actual diameter, is wear. Are you measuring the diameter of the tires that you have currently on the trailer.........that will have less tread now since they are used......as compared to a new tire specifications on a chart?

[fonzie]

I replaced mine with GoodYear Marathon and either load range c or d will fit, same radius at 28.3 inches ( same as Trail Express)

See link below. Go to tire selector and then marathon to see chart.

Goodyear RV Tires

[dcheatwood]

Originally Posted by ependydad

I do NOT have torsion axles, but I can say that my tires are about an inch and a quarter apart from each other.

E. Do you have torsion axles? Any rubbing?

[dcheatwood]

Originally Posted by dcheatwood

E. Do you have torsion axles? Any rubbing?

Disregard. I see noe. Thx.

[dcheatwood]

May have to sneak out with tail tucked. I measured from ground up. Didn't consider squish factor. Mine measured 26.5" from ground. Will remeasure horizontal tomorrow. What a duh! Moment.

[OldCoot]

Originally Posted by dcheatwood

May have to sneak out with tail tucked. I measured from ground up. Didn't consider squish factor. Mine measured 26.5" from ground. Will remeasure horizontal tomorrow. What a duh! Moment.

If you insist on measuring, measure the circumference of the spare if it is the same size and divide that measurement by pi (3.1416) or jack up a wheel and measure it's circumference.