The closed drivelines on the 52 1/2 ton had 4.11 gears for sure. However you truck now has an open drive and it still has higher than you would like rpm's corrrect? While the expense of changing the old rear over to 3:55's gears in the old closed tube axel is an option and expensive. You might want to determine what the rear you are now driving has, so you have a starting point. One of the easiest methods is to pull the rear cover and count the teeth on the ring gear and the pinion. Divide out and this will give you the exact ratio. A good all around gear is 3:08. Try and get a newer rear aprox the same width as the current open driveline. Late model chevy trucks are nice and many of the two wheel drive rears are 3:08. Look around at the pick-and-pulls. While you are out there looking try and get some S-10 rear lower shock mounts. Good luck.

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