BFL13 wrote:
Phil, a nitpic---the back duallies don't get the full 2680 as when single.
Right you are - if one agrees with what's published for single versus dual tire ratings. That was an oversight on my part (not enough morning coffee) ... because I intended to seem to agree with what's published.
HOWEVER, maybe deep down inside I don't agree with what's published about the dual tire versus single tire load carrying differences - because in certain applications it doesn't pass the common sense intuition smell test.
Why should dual versus single tire arrangements list different load carrying capacities ... if 1) the tires in dual configuration never touch, and 2) the tires in dual configuation still have adequate air flow between them so as to provide (real close to) the same cooling as a tire in single configuration?
To better help with 1) and 2) in my E450 MH's situation so as to keep the rear duallies inherent strength intact under a variety of situations - for all six tires I changed from the stock Load Range E 225/75R16 tire size to the Load Range E 215/85R16 tire size. The E450's stock rims and wheel well clearances presented no issues with this slightly narrower and taller tire size.
Since the 215/85R16 size is slightly narrower, the inner sidewalls of the tires are further from each other. This insures that the sidewalls never touch and also insures better cooling air flow between the tires. As a bonus (the most important to me), the taller profile also provides approximately 3/4 inch more ground clearance everywhere on the motorhome's underside.
I need a solid engineering explanation as to why the weight carrying difference between single tire service and dual tire service exists under all usage conditions? It's not intuitive.
