Ken: Those old AD COE trucks are way cool. Oly is correct, in that all AD trucks over 1.5 ton (11,500 GVW) used the dipper 235 engine.
The same 4 speed transmission was used on all trucks from 1/2 ton thru the 2 1/2 ton models. These trucks could be ordered with the RPO 5 speed
Spicer transmission also. I believe there was also a special production option "heavy duty" 5 speed box available. Rears were either GM or the Eaton option, both available as standard or in two speed form.
As far as I know the only differences between the small and larger truck transmissions was the addition of the parking brake/bracket assembly and the brake drum assembly on the tail. The 1 ton and 1 1/2 ton trans brake used a small "shoe" on the drums internal surface. The 2 ton and larger trucks used a band brake on the drums outer surface. The shift lever was also different in that the COE doghouse was in the way, so the lever is bent over to the left.
The cooling system on the COE is different from the conventional trucks. If I remember, I think the thermostat housing is different, comes off at side angle instead of forward. I think the radiators have a larger core to compensate for decreased airflow. Also used a 5 blade fan on the waterpump and had a fan shroud that was about 10 inches long.
There is a guy that I know, bought a few parts and a truck from him several years ago. His name is Clark Huff. He has about 100 old Chevy trucks from the 40's and 50's. He probably has more knowledge of old COE's than anyone I can think of. Check out his site and I think he'll set things straight.
Go to:
www.antiquetractorsandtrucks.com Hope this helps.
Think Chevy!
:p
