Trailer wheels like the # AM3H350 that you referenced have a zero offset which means the mounting flange of the wheel is exactly in the middle of the wheel. That means the backspacing of this would be 4.15 inches since this tire has a section width of 8.3 inches.
So you'd need 4.15 inches of clearance between the hub face on your axle and the frame of the trailer. view full answer...
We do have engineering diagrams for the Timbren Axle-Less Trailer Suspension System # A35RD545E that you referenced, and we do show these on our product page. If you scroll down a bit you'll find several measured drawings of this system with dimensions and mounting points.
I have also linked one of these images for your review.
This kit installs either by welding or bolting to your trailer frame and two sets can be used for a tandem-type application (but not three). Included are built-in... view full answer...
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