Hanger Kit and Slipper Spring Spacing for Tandem 7,000 lb Axles to Add 16 Inch Wheels

Question:

I have an Econoline 7 ton trailer with 14.5 8 lug wheels I want to replace with 16 inch wheels and tires. Tired of the lack of quality with the 14.5 tires and there seems to not be any 15 inch 8-lug options. Current Axle spacing is 32 inch and there is only 3 inch between the top of the tire and bottom of the trailer deck. So it seems that I need to replace the current hangers with taller ones and spread the axles further apart. Not sure if the axles should be 36 inch or 38 inch apart.? Would hanger kit AP216-H238 with SP232275 springs be the right set up.? Looks like hanger spacing would be 30.5 inch according to other posts but they dont mention wheel/tire size. Thanks

asked by: Jerrold H

Helpful Expert Reply:

The spacing is going to depend on the size of your tires, so let's start with that. For a 16 inch wheel/tire combo with an 8 on 6-1/2" bolt pattern the best option is a ST235/80R16 size tire with a load range of G to handle the capacity of your trailer. . A ST235/80R16 tire will measure nearly 31 inches in diameter so if your axles centers are spaced 36 inches apart you will have plenty of room.

For the slipper springs you were right on with the 5-Leaf Slipper Spring w/ Hook End for 7,000-lb Trailer Axles # e74SR and for the hanger kit you will need the Tandem-Axle Trailer Hanger Kit for 2" Slipper Springs - 13-1/8" Long Equalizers # AP216-H238.

This combination will give you the necessary spacing to add the larger wheel and tires you wanted and the center hangers are 4-1/2 inches tall, which is more than your current set up. You may be able to use these with ST235/80R16 tires, which measure 30.7" in diameter.

The wheel and tire combo I strongly recommend is from Provider because they are high-quality, 14-ply tires with a tread depth bar that will keep you appraised of how much life is on your tires. They also have one of the best warranties in the industry, covering two years and including emergency tire change if necessary.

These tires have a 4,080 lb capacity when inflated to 110 psi and there are three styles to choose from depending on how you want your trailer to look:

- Provider ST235/80R16 Radial Trailer Tire w/ 16" White Spoke Wheel # A16R80GWS
- Provider ST235/80R16 Radial Tire w 16" Viking Aluminum Wheel # A16RG8BMMFL80

I have added links to video reviews of these parts for you as well as a link to a help article on slipper spring trailer suspension and how to determine wheel bolt pattern.