Mike - After a little more digging through resources, it looks like the initial offering of a V-8 (265) and 6 speed Powermatic transmission package was in the 1956 Chevy LCF line HERE.

As '56 was the first year offered, the 1956 Chevrolet Truck Engineering Features pamphlet has a detailed section with most anything you may want to know about the "Powermatic". By '59, the information wasn't included in that year's pamphlet as it was considered "old news".

I couldn't find anything that indicated '59 LCF's (5000-9000 Series Trucks) were equipped with 3.73 or 3.55 rear axle ratio's. The axle ratios for both standard/optional single speed and 2 speed rear ends are specified in the previoulsy linked 1959 Chevrolet truck Data PDF.

So the "beast" with a V-8 and 6 speed Powermatic's exist, just not with either of the axle ratios you mentions. wink

~ Dan
1951 Chevy 3 window 3100
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