According to the calculators a .68 5th gear will drop my highway rpm from 3000 to 1700 at 60mph
Funny, my pencil and paper says that 3000 x 0.68 = 2040 rpm.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
