Check out the Blue Ox Blue Ox High-Low Adapter, part # BX88241. This adapter has a 7" Rise and is 12" Long. The tongue weight capacity for part # BX88241 is 10 percent of the towing capacity. For this adapter, the tongue weight capacity would be 1,000 lbs. High-low adapters were designed for flat towing , but Blue Ox said it could support your 600 lb rock salt spreader assuming the trailer hitch on your vehicle can support that much tongue weight as well.
The best option would be to mount... view full answer...
I have attached a diagram detailing the dimensions of the Sam Replacement 20" Spinner for SaltDogg Salt Spreader - Counterclockwise item # 3379240020 you were asking about. It has a 2/34" bolt pattern. We do not have any 3.5" bolt patterns. view full answer...
We have a Replacement Auger Bearing for Tailgate Salt Spreader # 337AB2H16F which has 3 inches from bolt hole center to bolt hole center. The inner diameter is 1 inch so if that matches then you'd be totally good! view full answer...
The inner channel width of the Curt Adjustable ball mount part # C45901 and it's replacement shank part # C45917 is 3 inches and the outer width is 3-3/4 inches. view full answer...