I put 19.5 on my crew cab dually F-350 (1974 model) it cost me about 2000.00 for the complete change over. This was 6 years ago or so and I average about 75,000 to 85,000 per set and the 14 ply rating on them make hauling heavy or towing a dream also when it is empty it is a nightmare of a ride. It bounces at every expansion strip on the road the ride is horrible.