Studebaker Steering Box Info.
Studebakers used a few different models of steering gearbox over the years, from primarily two sources: Ross and Saginaw.The Ross boxes were cam-and-lever gears that were used throughout the 1950s and into the 60s on almost all Studebaker cars and trucks.Saginaw boxes were more modern recirculating-ball types used on some 50's Studes and post-63 Lark-types. Most people agree that the Saginaw boxes have less steering effort and are easier to repair.
Anyway, there's an easy way to tell which kind of steering gear your Studebaker has, as explained by SDC Technical Editor Bob Palma on the SDC Forum:
To determine if you have a Ross Box, see what size wrench is needed to remove the square pipe plug at the check/fill hole on top of the box. If the pipe plug requires a 3/8" or 7/16" wrench, it is a Ross box. If the plug is near the very top of the box and requires a 1/2" or 9/16" wrench, it is a Saginaw unit (thank goodness!)
Why does it matter? Primarily because the two different types of manual units take two different types of lubrication.
The Saginaw boxes are easy to lube: they take standard chassis grease. You can literally pull the plug and pump in a few squeezes of chassis lube from your grease gun to top them off. The Ross boxes, however, take an 80w or 90w gear oil with EP (ex/treme pressure) additives; Kendall 999 was the preferred grease, but Kendall is no longer around. So, what to use?
Studebaker International to the rescue, with p/n 801651 Semi-Fluid Steering Grease. This is heavy stuff that can also be used as assembly lubricant when you're repairing a Ross or Saginaw box, or to refill a Saginaw after service in lieu of the special S-P steering lube that's long out of production.
Oh, and Jeff Tangemann of Lincoln, Nebraska writes that "a steering shaft out of a circa 68 Chevy truck will fit in a Lark Saginaw steering box." Good to know!