My feelings exactly F-250 Restorer. I love working on my dent and improving it. It beats going to a casino or being holed up in a bar though it’s just as expensive. 😎 It’s just good all around therapy.

 

Find a old car or pickup 3 speed manual transmission, 3rd is high or straight through, 2nd is like 1.45 to 1, flip it backwards, make frame mounts, put U-joints on it, connect it in rear driveline, just use 2-3 lever, when in 3rd, you're just in high, but when you slip it into it's 2nd, that 1.45 to 1 is reversed, it's now a 0.689 to 1 overdrive.
How they done it a lot in old days …. like when they made tractors from old car & truck parts.

 

Years ago I read a fascinating thread about Brownie aux OD's and how to make your own OD, and by using two transmissions, etc. It was amazing and I wish I understood it all. I went looking for info because I had an old Borg Warner R-10 three speed OD with electric OD. The trans supplied either three low or three high gears. My research revealed that parts were hard to come by, especially replacement gears, and since the trans with non-synchronized, gears were severely worn. I sold it and the guy that bought it said he only wanted the tail section, the OD, which he was going to mount separate from the trans he had. That made go and read up.

 

85e150, thanks for the article threads! Very informative

 

I have a 6041 spicer auxiliary in my 79 F350.It works great,two stick choice of 16 forward gear and 4 in reverse.Truck has 4.10s in the rear and in overdrive takes it down to a 3.52 final drive.Also you can't flip a 3 or 4 speed backwards.They will not get the proper lubrication and you will break the input shafts.They aren't designed to work that way.

 

Can you expand on the details of this? Why would you be building up more heat when the transmission is turning SLOWER?

 

Overdrive is a higher gear so it puts more load on the engine which makes the converter slip more.