The 15" 5 lug rim, white steel "wagon" wheel
so common on many trailers today kind of limits your tire gvw ratings....carlise, towmasters, marathons...i think the failures we keep hearing about are a case of overloaded and underinflated tires.
Look at the marathon chart I copy/pasted below when you step up to a 16" rim and tire!! Multiply the gvw number by 4 since most trailers have 4 tires.and remember to run the maximun recomended inflation presure to achieve the maximun gvw rating.
I like and run 16" rims and tires on my trailer.
Marathon®
THE LONG RUNNING RADIAL DESIGN SPECIFICALLY FOR TRAILER TOWING
Features
Specifically designed to make trailer towing easier, more stable and more economical
Sizes available for travel trailers, pop-up campers, boat trailers and fifth wheel trailers
Delivers dependable highway stability, positive traction and long lasting wear
Load Inflation Tables | Warranty | Size Conversion Chart
This tire is suitable for all Trailer applications
Helpful Information On Tires Used In Towing Applications - PDF
SPECIFICATIONS
Tire Size Load Range Side
wall Tread Depth (32s) Apprvd. Rim Widths Meas. Rim Width New Tire Width Outside Diameter Tread Width Static Loaded Radius Revs per Mile Max Load at Infla. (PSI) Single
ST175/80R13 C BL 9 4.5-5.5 5.00 6.9 24.0 4.9 10.6 870
1360@50
ST185/80R13 C BL 9 4.5-6.0 5.00 7.2 24.6 5.2 10.8 851
1480@50
ST205/75R14 C BL 10 5.0-6.5 5.50 7.9 26.1 5.6 11.6 800
1760@50
ST205/75R14 C OWL 10 5.0-6.5 5.50 7.9 26.1 5.6 11.6 800
1760@50
ST215/75R14 C OWL 10 5.5-7.0 6.00 8.5 26.6 6.0 11.8 783
1870@50
ST215/75R14 C BL 10 5.5-7.0 6.00 8.5 26.6 6.0 11.8 783
1870@50
ST205/75R15 C BL 9 5.0-6.5 5.50 7.9 27.1 5.6 12.0 770
1820@50
ST225/75R15 C BL 10 6.0-7.0 6.00 8.7 28.3 6.2 12.5 738
2150@50
ST225/75R15 D BL 10 6.0-7.0 6.00 8.7 28.3 6.2 12.5 738
2540@65
ST235/80R16 D BSL 10 6.0-7.5 6.50 9.2 30.7 6.0 13.9 673
3000@65
ST235/80R16 E BSL 10 6.0-7.5 6.50 9.2 30.7 6.0 14.1 675
3420@80
Fabric/Steel Construction