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**jocko** · 12-21-2021, 10:39 PM

Geezer and 70Stovebolt are spot on.
Exact numbers by the math for your transmission final drive (1:1), rear end (3.73), and tire dia (29.1" for 255/70/15) combo:

50 mph=2153 RPM
60 mph=2584 RPM
70 mph=3015 RPM

12-21-2021, 10:39 PM	#10
jocko Senior Member Join Date: Oct 2009 Location: Godley, TX Posts: 17,998	Re: 3 speed RPM question Geezer and 70Stovebolt are spot on. Exact numbers by the math for your transmission final drive (1:1), rear end (3.73), and tire dia (29.1" for 255/70/15) combo: 50 mph=2153 RPM 60 mph=2584 RPM 70 mph=3015 RPM