Pressure Rating for Rims

[hehbr]

I have a Windjammer 3008W with 15 inch wheels. Does anyone know the pressure rating for the rims? The tires on there now are load range C with 50 psi max inflation and replacement D or E rated tires have inflation pressures up to 80 psi. Don't want to overload the rims when I change tires. Thanks.

[bakken]

If you have the aluminum rims, I believe they are good for 65 psi.
Even if you get load range E tires, you don't have to run them at full pressure. But D-rated tires should give you enough load carrying capacity for some peace of mind.

[Iggy]

If you have a picture of the rims it could help. If they are the aluminum light weight type I have seen with 15" load rand C tires the rims are only rated to 65psi and no higher.

You can verify by a few letters stamped on the rim. Maybe inside back of rim but if it starts with a J that is only rated for 65psi max.
Now you still can put the tires you want on it if they fit but only 65 psi max which still may work for you.
Good Luck

[hehbr]

Yes, I have the aluminum rims and D rated tires are good for 2540 pounds each for a total of 10160 and the trailer GVWR is 8600 but I won't get near that. Thanks.

[Herk7769]

It has been a while since I had the rims off, but I seem to recall my white steel rims are stamped 60 PSI Max. The spare is easy(er) to get to and I will look tomorrow.

I have D rated Marathons on them and inflate them to 58 PSI Cold. This is 10 PSI over the actual load required pressure of 48 PSI.

The camper came with C rated Carlisle's and needed to be at max (50 PSI) all the time.

[House97]

Originally Posted by herk7769

It has been a while since I had the rims off, but I seem to recall my white steel rims are stamped 60 PSI Max. The spare is easy(er) to get to and I will look tomorrow.

I have D rated Marathons on them and inflate them to 58 PSI Cold. This is 10 PSI over the actual load required pressure of 48 PSI.

The camper came with C rated Carlisle's and needed to be at max (50 PSI) all the time.

Lou,
I thought that you had once posted an index of load/tire pressure on a related thread, but I can't find it.
I just had some load range D tires put on, now I'm wondering to what pressure they should be inflated.

[RodeoGeorge]

Here is a link to the MAXXIS Chart. I've checked it against the Goodyear Marathon, and they are identical.

http://www.maxxis.com/Repository/Files/m8008load.pdf

RodeoGeorge

[Herk7769]

Here is the Goodyear chart:

[Witch Doctor]

Originally Posted by herk7769

It has been a while since I had the rims off, but I seem to recall my white steel rims are stamped 60 PSI Max. The spare is easy(er) to get to and I will look tomorrow.

I have D rated Marathons on them and inflate them to 58 PSI Cold. This is 10 PSI over the actual load required pressure of 48 PSI.

The camper came with C rated Carlisle's and needed to be at max (50 PSI) all the time.

herk, I 'm confused are you saying that you run your tires under the cold PSI recommend? I always thought that the tire needed to be at the rated PSI, if for nothing else the wear pattern from being under inflated...

[Herk7769]

Originally Posted by gljurczyk

herk, I 'm confused are you saying that you run your tires under the cold PSI recommend? I always thought that the tire needed to be at the rated PSI, if for nothing else the wear pattern from being under inflated...

"Under/over inflated" is based on the ACTUAL load on the tire. The camper placard pressures are based on the maximum gross weight the camper is rated at. If you are loaded to the GVWR and the placard says 50 PSI and the tires are rated for their maximum load at 50 PSI; then that is what you should run.

IF (and I say again WEIGH your camper!) you have less than the rated load on your tire, THEN running the maximum PSI will result in an "over hard" tire.

This results in a "ballooned" tire and a smaller tread footprint; center tread wear; and a hard, bouncy ride for the camper.

Overloading (or under inflating for the actual load) the camper's tire (even at max PSI) will result in a squashed tread footprint with a lighter pressure in the center of the footprint and the majority of the tire's load on the edges (inner and outer side tread wear), insufficient sidewall strength to resist road debris impact, a "squirmy" ride, and the potential to roll the tire off the rim in a hard pivot turn.

"Optimum" tread contact (even pressure across the footprint) is obtained at the exact cold inflation pressure for the actual load on the tire. It will allow optimum pivot turn performance, minimum camper bounce (less broken dishes!), and a lower rolling friction resulting in better fuel economy (although harder is better here - see above for the over hard tire downside).

Manufacturers run tests on their tires to determine the optimum pressure for each load the tire is rated for (up to the maximum for that load range).
They publish this as a chart (see other posts).

Upgrading to a load range higher than shipped allows you to use exactly the correct cold inflation pressure for your load AND increase that pressure up to 10 PSI (no higher than the rim rating) to increase the speed rating of the tire.
Herk

[Witch Doctor]

Herk, My axle weight is 7340 it has been weighted at a cat scale. According to the Maxxis load rating then I should be under 50 lbs. PSI is that correct which would put me at a max of a C rated trier, I have Marathons D rated. So if I understand your explanation my tires should be ran at 60 PSI that would keep me under the rim rating of 65 lbs and allow me to drive at 70 mph. Is this correct? Thanks for your answer.

[Herk7769]

Originally Posted by gljurczyk

Herk, My axle weight is 7340 it has been weighted at a cat scale. According to the Maxxis load rating then I should be under 50 lbs. PSI is that correct which would put me at a max of a C rated trier, I have Marathons D rated. So if I understand your explanation my tires should be ran at 60 PSI that would keep me under the rim rating of 65 lbs and allow me to drive at 70 mph. Is this correct? Thanks for your answer.

Yes. (only considering the tires and not driving 70 pulling a camper)
That is my understanding of the available data.

I have driven at speeds as high as 70 (for short periods) but only when traffic required it for safety or passing expeditiously slower truck traffic with a line of cars behind me.

[Old car]

I have the Windjammer 3008W as well and last fall we had tire issues. I sent an email to the aluminum wheel manufacturer and asked about pressure ratings. They told me the rims can handle Load D (65 psi) without issue but not to go over the weight rating. I did not ask about going to Load E since I was putting D on the trailer.