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buzzcop63 · 06-21-2013, 09:25 AM

Tires:
Looking at Power King Towmax STR web sight I found the tires on my 2012 Cougar 27' TT, (model 24RKSWE) ST225/75R15LRD are rated at Dual Max Load 2,200 Lb at 65PSI. My trailer max weight is shown at 7,200Lb by Keystone. If I want 20% safety margin for my 7,200Lb trailer I would add 1,440Lb, then I would need four tires who's combined max rating would be 8,640Lb and the Power King Towmax four tires combined are 8,800Lb. I have my safety margin for my unit.
However if you look at two additional TT models in Keystone 1/2 ton Series that are heavier then my unit, 25RLSWE and 26BHSWE which utilize the same tire we find those two trailers have a max weight rating of 7,800Lb. 20% of 7,800 would be 1,560Lb or 9,360Lb combined total of the four tires when they are only rated for a max of 8,800Lb this would be about 13% safety margin over max trailer weight! I suspect that for 5th wheels this could well be the same, the safety margin drops as the same tire is used on heavier units.

06-21-2013, 09:25 AM	#1
buzzcop63 Senior Member Join Date: Apr 2013 Location: Beaverton Posts: 309	Tires Tires: Looking at Power King Towmax STR web sight I found the tires on my 2012 Cougar 27' TT, (model 24RKSWE) ST225/75R15LRD are rated at Dual Max Load 2,200 Lb at 65PSI. My trailer max weight is shown at 7,200Lb by Keystone. If I want 20% safety margin for my 7,200Lb trailer I would add 1,440Lb, then I would need four tires who's combined max rating would be 8,640Lb and the Power King Towmax four tires combined are 8,800Lb. I have my safety margin for my unit. However if you look at two additional TT models in Keystone 1/2 ton Series that are heavier then my unit, 25RLSWE and 26BHSWE which utilize the same tire we find those two trailers have a max weight rating of 7,800Lb. 20% of 7,800 would be 1,560Lb or 9,360Lb combined total of the four tires when they are only rated for a max of 8,800Lb this would be about 13% safety margin over max trailer weight! I suspect that for 5th wheels this could well be the same, the safety margin drops as the same tire is used on heavier units.