Your truck has the stock original steering box. It's not unusual for them to leak. It's not likely that a gasket will solve the problem. There are numerous posts regarding what to use in steering boxes. They range from chassis grease to a mixture of gear oil and grease to a product called cornhead grease. Generally if there is some wear, regular gear oil will run out fairly quickly. If the steering box seems tight you can try using one of the aforementioned products. Otherwise the unit will probably need to be rebuilt.
Fred

Last edited by rfs56trk; 09/08/2014 4:01 PM.

1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine