Originally Posted by hardshell
If I leave the original gears in this rear of the truck, What kind of top speed or maximum traveling speed should I expect?
The top comfortable speed from the original 4.11 gear set, would be about 50 mph.
Changing tire size will also help a little in lowering engine RPM.
But if your going to drive it around the farm leave the 4.11 gears set in there.
Check your original Axle gear ratio in 1950 Truck Specifications PDF page 58 under Rear Axles.

Sorry on previous post, I thought you were asking about the top speed for the 3.55 gears set.