1940 Mercury 3 speed manual trans.

jayvee34

Senior Member
I converted my 40 merc to a c-4 automatic trans. The 3 speed manual side loader # 99A-2I2635. My question is will it fit all Flathead motors from1940
to 1948 cars? Also will it fit 1/2 ton trucks up to 1948?
Thanks for answers, John:)
 
Yes it will . . . all the flathead blocks have the same bell housing bolt-pattern . . . 32 - 48. It will also work with later 49-53 flatheads as long as you have the correct bell-housing, clutch release setup, etc..

On the pickups, there is something to note: This transmission was for a torque-tube setup (closed drive), while many of the pickups had an open driveshaft type of configuration. If the pickup has an open drive, then the 40 Merc transmission would need to be converted to open drive (which requires a new main-shaft, new rear mount, speedo drive, etc). You can usually find the open-drive components on eBay, though it is very important that the main drive shaft NOT have wear on the front bearing surface.
 
Yes it will . . . all the flathead blocks have the same bell housing bolt-pattern . . . 32 - 48. It will also work with later 49-53 flatheads as long as you have the correct bell-housing, clutch release setup, etc..

On the pickups, there is something to note: This transmission was for a torque-tube setup (closed drive), while many of the pickups had an open driveshaft type of configuration. If the pickup has an open drive, then the 40 Merc transmission would need to be converted to open drive (which requires a new main-shaft, new rear mount, speedo drive, etc). You can usually find the open-drive components on eBay, though it is very important that the main drive shaft NOT have wear on the front bearing surface.

Thanks very much for answering my question. I thought I knew but was not
sure. Thanks again.
 
Some of the early Mercury cars (after 1939) have the 15/29 tooth input match up. They are a bit different then the regular Ford 16/28 input set otherwise they are pretty much the same as any other Ford side loader with the late gear & synchro set up. A lot of folks purchase the side loader transmissions just for the parts inside. They can be used to update an early top loader with the old style synchro as long as the correct 2nd/high shift fork is used. The 15/29 input set works well with tall ring & pinion gears like the 3.54:1 for good get up and go on the highway as long as the car isn't too heavy.
 
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Some of the early Mercury cars (after 1939) have the 15/29 tooth input match up. They are a bit different then the regular Ford 16/28 input set otherwise they are pretty much the same as any other Ford side loader with the late gear & synchro set up. A lot of folks purchase the side loader transmissions just for the parts inside. They can be used to update an early top loader with the old style synchro as long as the correct 2nd/high shift fork is used. The 15/29 input set works well with tall ring & pinion gears like the 3.54:1 for good get up and go on the highway as long as the car isn't too heavy.

I still have the torque tube, drive shaft, ring and pinion gear. R & P is a 3:54:1
(11/39). Thanks for the information.
 
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