VCCA Home Forums TECHNICAL - GENERAL Mechanical - Engine, Trans, etc Rear end gear ratio on a 1930

Did all 1930 Chevys have the same gear ratio? If so what is it?
How can you determine the ratio?

The 1930 through 1936 cars had a 4.11 ratio as standard equipment. The 1929 had a 3.82.
The 1930 engine was running slower at 50 MPH than a 1936 as an example due to the 1930s' larger diameter wheels/tires.

Also, other sources show 4.10 for 1930 and 3.81 for 1929.

Thanks for the information guys. How can I tell which it is? I have the gears out of the housing. They are still attached to the torque tube.

The 1929 had 42 teeth on the ring gear and 11 teeth on the pinion gear.
42 divided by 11 = 3.818
The 1930 had 37 teeth on the ring gear and 9 teeth on the pinion gear.
37 divided by 9 = 4.111

Chev Nut, Thank you for the information. Rich

Actually, the 1930 passenger cars had a ring gear with 41 teeth and a pinion with 10 teeth, which is a 4.10 gear ratio. This gear ratio was used in 1930 and 1931. In 1932 there were three ring and pinion gears available; the standard 41-10, the special 39-9 and a 37-9 that came out late in the year.

My 1939 parts book shows just the 9-37 gear set with part #364244.????

Right....that is a much later parts book and the gear set shown there is a retrofit. The 1930, 1931, 1932 and 1933 parts books show the gear set applications that I listed above. The only gear set offered in 1930 was the 4.10 and the part number was 362737.

Part number 364244 is listed in the 1933 parts book as a 37-9 gear set and the application shown is 1932 only.