I don't know what it is, but here are the usual ranges and general applications (by no means exact or scientific)

0.62 - 0.65 (usually only as a second overdrive "double over") old big trucks and new pickups
0.73 - 0.75 very common automotive and light truck, newer big trucks
0.79 - 0.86 very common big truck

Grigg



•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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