Hard to Pick a tire for TT

sgrizzle wrote:


Radial ST 225/75 R15D (F-108)? They are 6 years old and we are headed out this spring on about a 3,000 mile camping trip over the rockies and to the Moab area...I have heard trailer tires need to be replaced every so many years, whetherthey look worn or not.

I am considering replacing them with LT tires.

My Trailer:
GVWR is 7900 lbs.
GAWR (each Axle) is 4,400 lbs.
Max Cargo is 1,460 lbs.

How do I choose the best match in a LT tire. I have tried looking at Tire Rack and michelin sites and it gets pretty confusing. Thanks for your help!

If you are at 6 years, IMO your time is up to change. Good choice to change them before your next trip, including the spare.

A good part of understanding tires failures is proper loading with reserve capacity and proper air pressure (at max side wall pressure cold). With the camper fully loaded, including water if you tow with water down the highway, you need to find a scale setup that can weigh each tire as they are not all loaded equal. Then work to get a tire or reduce weight at that wheel to get to 20% extra load capacity over the heaviest loaded tire.

I can see by your D rated tires on a camper that light, as long as you are not over the weight ratings your setup is a lot better then most.

As far as a brand of ST tire, I have had acceptable luck with Maxxis, however 5 years is going to be about it before side walls and tread cracks are pretty advancing along.

If you want to go to LT tires, there is some home work and work involved. You can see my upgrade here to know if this is something you want to take on. Your camper may be setup different and you do not have to fiddle so much with wheel well clearance.

ST225/75R15 to LT225/75R16 Conversion

Hope this helps and good luck

John

Our local tire shop did not stock Maxxis but ordered them for us and they came in within a few days.

205/75R14 Load C 6 ply 1760 lbs double steel belted

We had them balanced

I think Cooper makes a LT235/75-15D tire. I am running that size now.

My trailer came with D's and I replaced them with Towmax STR E rated tires. I run 80# in them.

My 6 lug rims only give a weight rating, not a PSI rating. I elected to go with the E rated tire with less than 80 PSI and matched the psi to my wheel rating based on the Maxxis chart. I still get a little more reserve and have a heavier tire.

You should double check this but I am thinking the 6 lug 15" rims are good for 80psi. The 5 lugs ae not.

dodge guy wrote:
They don`t make an "D" or "E" rated LT tire in a 15". I went with Carlisle ST "E" rated tires. very glad I did despite what people post about them. all the failures in my research were in the "C" rated tires.

All 5 that came with my TT were LR D and failed on their own.
I've read plenty of posts about the higher LR's failing.

Good luck.

dodge guy wrote:
They don`t make an "D" or "E" rated LT tire in a 15". I went with Carlisle ST "E" rated tires. very glad I did despite what people post about them. all the failures in my research were in the "C" rated tires.

With the E tires what pressure do you have in them? If you went from C to E tires did you find the trailer has less sway?

They don`t make an "D" or "E" rated LT tire in a 15". I went with Carlisle ST "E" rated tires. very glad I did despite what people post about them. all the failures in my research were in the "C" rated tires.

Get the Maxxiss' and forget about them.