Another Tire Question

[shakyjay]

Time for new tires. Currently have ST205/75/15C's. They are the originals and up til now have been fine however age is taking it's toll and sidewalls are cracking. Stopped at America's Tire. Seems they now are not stocking the Towmasters which was one of the tires I was considering. Instead they have gone back to stocking the Carlisles that supposedly have been redesigned. I have done some research and it appears the new RH does have some improvements. After much discussion with the salesman who actually said he is running the Carlisles on his 13,500 lb. fifth wheel. He recommended that if I have the clearance to go with a Carlisle ST225/75/15 E rated tire. Supposedly it should only require about an 1.25 inches more of clearance. So my options are just replace with original size and range in a ST205 or what my original intent was to go ST205 in a D range or go up to the ST225 in load range E. Price between the three is really not that much difference D range $50 more than C and ST225 $80 more than C. The other option I am considering is to have him order the Maxxis. Price for them in ST250/75/15C is about $100 more than the same Carlisle. He absolutely did not recommend Marathons and said he could order the Towmasters but really did not recommend them either.

So after all that I am simply looking for some input to help me decide which option would be the best. I do not tow full time. Actually now days the trailer sits more than it moves. What travels we do use it for are generally no more than a couple of hundred miles one way. Occasionally we may go a little further. I do not run heavy but would like a little cushion.

[LakeN]

Ran a set of Maxxis on a camper we recently traded. Very pleased with performance. They never ran hot and seem to be the best tire at this time. They may cost more but a cheap tire blowout can cause TT damage which in the end could be more costly. We plan to put new Maxxis on new camper before too long.

[JIMNLIN]

Agree with Larry. A trailer unlike the tow vehicle can have too much tire. The Rockwood is a ultra lite trailer and all show a 6k-7k GVWRs.

You didn't tell us what the trailers GVWR was or axle GAWRs but looking at '13 Rockwood web shows the biggest at a 7800 GVWR with a 1380 CCC figures about 1600 lbs per tire. Now add 15 percent for a nice capacity reserves and the the 205/75-15 C at 1820 lb work out fine.
Higher pressure 65 psi tires require higher 65 psi pressure rated wheels. You want to run the ST tire at its max pressures so the wheel will need to be be rated to use 65 psi. Some 15" wheels are rated to 50 or 65 or 75 and 80 psi.

No more than your trailer is on the road I would go with the 205/75-15 C at 50 psi. Brand is your choice as IMO a ST tire is still a ST tire and all brands have the same issues. Even the Maxxis ST8008 although they seem very popular at this time.

Or the new and improved Carlisle RH may actually be improved.

[LarryJM]

I agree with the 2K per tire and here are the load limits for 225 sized 15" ST tires

"C" - 2150
"D" - 2540
"E" - 2830

Issue is if your TT came with "C" then the rims might only be rated for 50# so "D" (65psi) and "E" (80psi) would/should need new rims as well. Both the C and D would be O.K., but IMO the E is overkill. Also an ST205R75x15(D) at 2150 would also be good. My choice would be the "D" at 2540 if your rims will take the PSI.

Larry

[brulaz]

Your trailer must be about 8000# GVWR.
For that I would want, as a bare minimum, a tire rated at 2000# each. (The tongue weight would provide some cushion)

The ST205/75R15C is only rated to 1820#, so I wouldn't go that route.

A ST225/75R15D is rated at 2540#. Much better.

As for Carlisles, maybe they are getting better, but I still don't trust them. I would order in Maxxis ST225/75R15D. They will be more expensive though ...

If you really like Roadmaster, you could order them over the internet and have the local shop put them on. But again I'd go with ST225/75R15D.