There's something else to think about. These old trucks most likely came with 7.50 x 20 tires. My buddy and I both have big bolts. Our trucks both have 261's ,both had the bigger incorrect tire size when we got the trucks. Living in the mountains we had troubles making it up hills without having to downshift to 2nd gear. He has been able to install the 7.50's and now has no problem keeping up a decent speed going up and down the hills.
