Thanks fellas! that gives me a rough idea , and is what I was looking for. To answer your questions.. I am running 6.50 x 16 tires. as far as I know it is a stock carb. and the steering seems to be in good shape. also think the brakes are as they should be too. so if I can get 12-22 mpg then it might be worth changing the ring and pinion and not sell the truck just yet... also does keeping the torque tube system help the truck keep its value or would it be more valuable with an upgrade to an open system?