wmtire

I looked at the requirements that a rim manufacturer is supposed to adhere to. I didn't find anything that states that they HAVE to put the air pressure and/or load designation on them, although some do. I guess that would make it too easy if they all did. I would safely assume that whatever air pressure the above trailer (ST) tire takes to carry 1870 pounds (or 50 psi according to Goodyears own spec charts) is also the maximum air pressure this particular rim is rated for also.

http://www.goodyear.com/rv/tirecare/...iontables.html

Even if the rim is capable of more air pressure, it still won't carry more weight. If you err on the side of caution, and keep your maximum tire air pressure in line with the maximum weight of the wheel, then you should always be safe on both counts..... especially if you don't know exactly what air pressure the rim is rated for.

If they manufactured the rim in accordance with the DOT regulation, then the "JCA" on Bill's wheel is most likely the company who made it in October of 2004. Sorry, I couldn't be of more help either.

Here is the reg referenced for our engineering or more useless trivia members:

12.2 RIM MARKING REQUIREMENTS (S5.2)
Rims must be marked with the following information in lettering not less than 3 millimeters in height, and impressed or embossed to a depth or height of not less than 0.125 millimeters. Items A through C must appear on the weather side of the rim.

A. A designation which indicates the source of rims's published nominal dimensions, as follows:

T - The Tire and Rim Association
E - The European Tyre and Rim Technical Organisation
J - Japan Automobile Tire Manufacturers Association, Inc.
D - Deutche Industrie Norm
B - British Standards Institution
S - Scandinavian Tire and Rim Organization
A - The Tyre and Rim Association of Australia
N - Independent listed with NHTSA

B. Rim Size Designation.

EXAMPLE: 20 x 5.50 or 20 x 5.5

C. The Symbol DOT. Manufacturer's certification that rim complies with all applicable FMVSS.

D. Manufacturer's Name, Trademark, or Symbol.

E. The month, day, and year or the month and year of manufacture, expressed either numerically or by use of a symbol.

EXAMPLE:
January 4, 1999 may be expressed as any of the following:
MO.-DAY-YEAR: 10499 (or) 104 (or) 99
99 104
MO.-YEAR: 199 (or) 1 (or) 99
99 1

Any manufacturer that elects to express the date of manufacture by means of a symbol shall notify NHTSA in writing.