1941 ford 1 1/2 ton with standered rear Axle , want to install 2 speed rear axle. It is a 4 speed will the 2 speed give it a better top end and by how munch? My second question is about improving the steering ability. It is hard to turn and there is alot of play. thanks for any info.

 

A two speed axle does not provide a taller final drive ratio, it provides an additional lower ratio (higher number) to handle heavy loads. Your single speed could have a 5.14/1, 5.83/1, or 6.67/1 final drive. If you have one of the lower sets (5.83 or 6.67) you might do a search for a donor 1948-1952 F-4 model that came stock with the 5.14/1. Stu

 

Welcome to FTE! The two speed axles for '40-'47 trucks and '48-'52 F5 trucks will be 5.83 in high and 8.11 in low. Your single speed axle is most likely 6.66, so a two speed will help the top end a little. With a good running stock flathead V8 and 7.50 to 8.25 tires your truck would easily run 55-60mph with a two speed in high range. Stopping these old trucks at highway speed though can be another matter.
These trucks generally steer very easy when moving, they can be hard to steer parking or setting still. Bad king pins can make one hard to steer. The ball thrust bearing under the axle on the king pin, may not be getting any grease or may be full of rust inside causing hard steering. Play in steering could be a number of problems, loose tie rod ends, loose drag link or steering gearbox worn or out of adjustment.
By the way, We do like pictures here!

 

My 1940 1-1/2 ton panel has the 5.14 rear end and 7.00-20 tires. I've used 40 MPH as a top speed the little I've driven it and it felt plenty enough. I do not think I would trust brakes or anything else at a faster speed. There are two numbers stamped in the bottom of the differential case; they are the tooth counts for the ring gear and pinion supplied from the factory. Divide the larger by the smaller to determine your rear end ratio.