My Gear Calculations

These are the gear calculations fo my 49 pickup. Calculate the speed of your Willys with its current gears and tires, or dream of new gears with my speed calculator.

T-90 Transmision
Rev3.798
1st2.798
2nd1.551
3rd1.000

Spicer 18
Transfer Case
Low2.46
High1.00

Spicer 25 front axle
Timken rear axle
Ring & Pinion1: 5.38
Saturn Overdrive
In0.75
Out1.00
Gear Ratios
engine revs/axle rev
Trans Direct Overdrive
Gear Low High Low High
R3.79850.26620.43337.69915.325
12.79837.03115.05327.77311.290
21.55120.5278.34415.3956.258
31.00013.2355.3809.9264.035

engine rpm * tire circumference in inches * 60
transmision gear * od gear * tranfercase gear * axle gear * 63360

Speed (mph) - low range
rpm60012001800240030003600
R-1-2-3-4-5-6
1134679
2358101316
34812162024
Speed (mph) - high range
rpm60012001800240030003600
R-3-5-8-10-13-16
14711141821
261319263239
3102030405060
Speed (mph) - low range overdrive
rpm60012001800240030003600
R-1-3-4-6-7-9
124681012
23710141721
351116222732
Speed (mph) - high range overdrive
rpm60012001800240030003600
R-3-7-10-14-17-21
15914192428
291726344351
3132740536680

Speed in High Range with & without Overdrive speed graph

© Richard B. Grover 1997 to 2006. Last updated: Saturday, March 24, 2001