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Old 03-13-2018, 06:01 PM   #11
JRTJH
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Originally Posted by CWtheMan View Post
IMO, those pictures confirm that the wheel is manufactured in two configurations. One is for four lug mounting and provides 2540# of load capacity with a maximum recommended PSI pressure of 65 PSI. The other configuration is for 5 lug mounting and provides 2830# of load capacity with a recommended maximum PSI pressure of 80 PSI.

NOTE: When increasing a tire's load capacity by increasing its PSI, one must insure the valve stem is certified for the higher PSI.
No, actually, one is for 5 lug and one is for 6 lug (not 4/5 lug configurations). The weight rating is based on the number of lug holes drilled in the casting. Six lugs will "hold more weight when attached to the hub" on the casting than 5 lugs, hence the higher rating. As for pressure, it's my understanding that there is no difference in PSI rating on either assembly, the higher pressure rating applies to all variations of the wheel when placed in production.

ADDED: You are correct, many valve stems used in passenger tire applications are only rated to 60 or 65 PSI and typically are not suitable for any D/E trailer tire applications. Heavy duty valve stems should always be used on all travel trailer applications. Metal valve stems are preferable to rubber or rubber coated stems for anything rated heavier than load range C. And, I'd suggest using HD valve stems even on them.
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Old 03-14-2018, 10:09 AM   #12
CWtheMan
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Quote:
Originally Posted by JRTJH View Post
No, actually, one is for 5 lug and one is for 6 lug (not 4/5 lug configurations). The weight rating is based on the number of lug holes drilled in the casting. Six lugs will "hold more weight when attached to the hub" on the casting than 5 lugs, hence the higher rating. As for pressure, it's my understanding that there is no difference in PSI rating on either assembly, the higher pressure rating applies to all variations of the wheel when placed in production.

ADDED: You are correct, many valve stems used in passenger tire applications are only rated to 60 or 65 PSI and typically are not suitable for any D/E trailer tire applications. Heavy duty valve stems should always be used on all travel trailer applications. Metal valve stems are preferable to rubber or rubber coated stems for anything rated heavier than load range C. And, I'd suggest using HD valve stems even on them.
Yup, I got the lug numbers wrong, sorry.

The PSI rating being displayed on the actual wheel, IMO, is a limiting factor for the fitment. Wheel specifications are certified by the Society of Automotive Engineers (SAE), so whatever is on the wheel would be part of their specs for that wheel configuration.

The U.S. Tire Manufacturer's association standards say, "do not exceed" a wheel's recommended maximum inflation pressure or its load capacity.

Referenced here on page #37 under NOTE.

https://www.ustires.org/sites/defaul...TruckTires.pdf
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