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| | | | Joined: Aug 2005 Posts: 277 'Bolter | | 'Bolter Joined: Aug 2005 Posts: 277 | The differential in my 39 has a good size piece missing from the end of one of the pinion gears. Probably been this way for years. I have a new ring and pinion but am hesitant to tackle the job. I assume that it would not be possible to replace just the pinion gear. The reason I even consider this is that I’m not certain how to go about replacing the ring gear. On 39, it was riveted to the carrier and I don’t know who, how or where to go about riveting on a ring gear. Is it possible to use bolts instead of rivets? Anyone had any similar experience. I would not have a problem replacing something like frame rivets but a ring gear? | | | | | Joined: Sep 2001 Posts: 208 Shop Shark | | Shop Shark Joined: Sep 2001 Posts: 208 | How about finding another complete rearend? My experience is limited to removing the diff to change the forward gasket on a '54.
Union, Justice and Confidence
| | | | | Joined: Feb 2006 Posts: 1,867 Shop Shark | | Shop Shark Joined: Feb 2006 Posts: 1,867 | I see no reason not to replace them with hardened bolts so long as there is clearence for the head.
You do not want to swap one gear or the other. They are lapped at the factory together for proper clearances, and should therefore be replaced as a set.
Jeff | | | | | Joined: Aug 2005 Posts: 277 'Bolter | | 'Bolter Joined: Aug 2005 Posts: 277 | Thanks for your input. I think Rustednuts is on target. Just hope there is room for bolts. Swampcat, swapping out the diff was my first idea. I have a complete 41 setting out in the parts pile. However, 1939 (37-39) is a bit of a different animal. Anything from 40 up uses a different propeller shaft/tongue tube. I could probably work around this but in 40, when they started bolting on the ring gear; everything got shifted ½”. This is reflected in the left axle being shorter than the right. My axles are both the same length. This means that the opening in the housing is centered in my diff and ½” offset in 40 and above. This limits my replacement possibilities to 39 (possibly 37-39) or maybe a complete 40 assembly axles and all (¾ ton only). BTW, mine is a ¾ ton. About the same as ½ ton in 39 with the addition of an extra short propeller/torque tube. It would be great if I could stumble across one within driving distance but what are the odds. | | | | | Joined: Feb 2006 Posts: 1,867 Shop Shark | | Shop Shark Joined: Feb 2006 Posts: 1,867 | Make sure you let us know how you proceed. And take some pictures to!  Good luck! Jeff | | |
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