Apache was a marketing term for light trucks, 31-38 series, Viking was the term used for medium duty trucks, 40-60 series and Spartan was for the heavy duty, 70-100 series, all 3 terms for the same year range:
started in 58 and went to 62 .... I've never seen anything to indicate those terms were used pre-58 although we do see a fair number of folks who think any TF truck is an "Apache", and I don't think you'll find the terms used in any GM documentation other than marketing phamplets
Bill
