VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1916-1922 - Model 490 490 rear axle bevel gears VS spiral gears.

I have been curious for quite a while now to find out when the spiral rear axle gears were introduced to the 490 model. I can't find the answer in any of my parts book. The 1916-1918 parts book only list the bevel straight cut gears, so it must be some time after 1918. My 1922 490 parts book lists a parts assembly to convert the bevel gears to the spiral gears. (Part number 24078)

According to "Early Chevrolet History, Passenger Cars 1912 to 1928 etc" (Floyd Clymer 1966) "A spiral type of ring gear and pinion replaced the old straight-cut type, and a new type of differential was used" from 1922 490 Models.

According to "Combined Part List Four Ninety and Superior Models, Effective on and after Februari 1st, 1924, the part number for the differential "For Use With Spiral Tooth Bevel Ring Gear) (Four-Ninety and Superior)" was 24761, , "Sold only with 24762".

I have not checked the rear gear on my 1922, but as I can hear no noice I guess it has spiral gears.