I had ask for help in a earlier post, locating a Spicer 5831A gear box. I have had a lot of response helping me locate one and others have given suggestion on the installation. I would like to Thank everyone for that. But It has been pointed out to me by several, that the 5831 may be a little small going behind a old 300 Mack engine, and that a 8000 series Spicer would be closer in line with the torque. NOW! the question is does anyone know where I might find something like a 8341 which is a 4 speed. I am not sure which model number was used for the 3 speed and would be interested in either one. I would like to still have the .73 Overdrive but again have been told that they are very rare. .84 will work. Any help would be appreciated.