Differential Pinion Gear Bearing Preload

[Bob Bidonde]

nkaminar in Post #3 is correct, the torques in the following service bulletins are the torques necessary to turn the pinion resulting from tightening the jam nuts. In other words, you tighten the jam nuts until the torque to turn the pinion is reached.

While researching the 1932 - 1937 Ford Service Bulletins, I stumbled upon information regarding the tightening torque for the Model "A's" pinion bearing:

• January - February 1934 Bulletin states, "The correct torque for the stub mounted pinion, as used in the Models A, B and early 18 is from 35 to 47 Inch-lbs."

• August 1934 Bulletin states, "The passenger drive pinion bearing adjustment has been reduced five inch-lbs. Correct adjustment for the various axles is as follows: Model 40 12 to 17 Inch Pounds; Model18 Straddle Pinion 12 to 17 Inch Pounds; Model B-18 Stub Pinion 15 to 20 Inch Pounds; Model A 15 to 20 Inch Pounds; Model AA Timken Type 12 to 16 Inch Pounds; Model BB 3/4 Floating 12 to 16; Model BB Full Floating 12 to 16 Inch Pounds.

No reasons were given for the reductions in torque.