New Trailer, New Tires and New Wheels

[JRTJH]

Today I pulled the wheels off our new Cougar to take them downtown to be balanced and to repack the wheel bearings in preparation of our pending trip. While I was cleaning the wheels I noticed the weight rating stamped on the back of each wheel. THERE ARE TWO !!!!!

One says "MAX LOAD 2150 LBS" and the other one says, "MAX LOAD 2830 LBS"

OK, the tires are ST225/75R/15 LRD and are rated at 2540 lbs at 65 PSI.

I know the axles are rated at 4400 lbs, so the wheels can not be rated at 2150, they wouldn't meet the requirement for the axle or the tires, so they are rated at 2830, but my question is: "Why are there two max weight ratings on the wheel?"--- I wouldn't think anyone would use cast wheels in a dual tire setup.... ??? But then, who knows...

Anyway, the tires are balanced, remounted on the trailer, properly inflated and properly torqued... Yes, I plan to stop at the rest area about 25 miles from home to retorque them..... Then every morning I'll check pressure and retorque the lug nuts. No I don't loosen them and retorque, I just set the wrench to 115 FtLbs and "click" each lug.

Any ideas on the dual weight rating?

[Ken / Claudia]

I am only making a guess, lower for single wheel, higher for duals. Lets see what a wheel expert says. I am not one.

[JRTJH]

That's what I initially thought, but then questioned that line of thinking after coming to the conclusion that I don't think anyone would "bury" a cast wheel on the inside of a set of duals. And, to my knowledge, there are no 15" dual trailer axle setups. At least I've never seen one. Most are 16" or 17.5" if arranged on a dual axle.

Like you, I'm interested in the "why are there two weight ratings" question.

[Javi]

Usually the alloy wheel is paired with a steel wheel on the inside.
Pretty sure that the dual ratings the lower one is for dual and the higher for single as you originally suspected.

[danimal]

Not an expert either but as long as we are speculating maybe that is for when a C range tire is installed? Another tidbit is my E trailer tires state load rating of 2850 and 2450 with dual tires.

[diugo]

The secret is the stamped part number that precedes each rating. The 5H-XXX is rated 2150 and the 6H-XXX is rated 2830. Hmmm, guess what H stands for? You got it: Hole. The more holes, the less load per hole, so the higher the rating. The six-hole rim is rated at 2830lb; the 5-hole version, 2150.

[JRTJH]

The secret is the stamped part number that precedes each rating. The 5H-XXX is rated 2150 and the 6H-XXX is rated 2830. Hmmm, guess what H stands for? You got it: Hole. The more holes, the less load per hole, so the higher the rating. The six-hole rim is rated at 2830lb; the 5-hole version, 2150.

Makes sense, thanks for the explanation. The local Goodyear tire store didn't have a clue, nor did the Firestone dealer. The truck accessories store just wanted to sell me bigger wheels and when I said these are brand new, then he wanted to sell me tire covers.... So, none of the local's had any explanation, yours seems more plausible than anything else I've heard or seen. Thanks

[hankpage]

The secret is the stamped part number that precedes each rating. The 5H-XXX is rated 2150 and the 6H-XXX is rated 2830. Hmmm, guess what H stands for? You got it: Hole. The more holes, the less load per hole, so the higher the rating. The six-hole rim is rated at 2830lb; the 5-hole version, 2150.

I have to agree with this because on a steel wheel the rim itself is rated for the pressure and then is welded to the center hub with different size and amount of lugs to carry the different weights. On higher pressure rated wheels the hole for the valve stem may be larger also so that the proper rating of stem is used. Also I don't think I have ever seen wheels used as duals with a 0 offset like those used on most trailers. (They would require extremely long studs and a spacer I would think. )

[CWtheMan]

This is sort of a footnote to what has already been said.

To the OP. Your rims are rated for 2830#. Says so right on the castings. So you can also upgrade to the ST225/75R15E when replacement time rolls around.

As for DOT regulations; They only say that the correct size by width, diameter, and load capacity must be used. The Society of Automotive Engineers (SAE) is tasked with the responsibility for load capacity and pressure ratings. Nowhere is it written that those figures have to be displayed on the rims. But, each rim must have a manufacturer identification and part/model number. That allows for individuals to contact the manufacturer about rim specifications.

CW

[JRTJH]

I have to agree with this because on a steel wheel the rim itself is rated for the pressure and then is welded to the center hub with different size and amount of lugs to carry the different weights. On higher pressure rated wheels the hole for the valve stem may be larger also so that the proper rating of stem is used. Also I don't think I have ever seen wheels used as duals with a 0 offset like those used on most trailers. (They would require extremely long studs and a spacer I would think. )

Good point, Hank. Neither have I. That would preclude using the wheel in a "dual configuration" so the lower number wouldn't be the load limit for dual use.

All my wheels are marked the same. There are actually 3 markings in sequence on each wheel followed by three additional markings. Here's what is on the wheels in seequence, cast into the spokes: 5H 114.3 / MAX LOAD / 2150 LBS. then the next three spokes: 6H 139.7 / MAX LOAD / 2830 LBS

There also is a DOT T ET 0 in one cast hole and A960 15X6J in another.

So, it seems that the 5 hole wheels used on Cougar XLites are rated at 2150 and the 6 hole wheels are rated at 2830.

Thanks all for your comments and help in answering this "puzzle" (tx)

[Ken / Claudia]

Good stuff to know, most of us learned something.