The Stovebolt Site Forums The Parking Lot Big Bolts auto trans in a 2 ton

Was an automatic trans available in a 2 ton truck. My dad has a 2 or 3 ton(old grain truck) AD body truck with a hood side emblem that says hydramatic. This is one of several trucks he bought years ago when he had a salvage yard. This truck is in weeds and trees and hard to get close to. Am I mistaken, seeing things or just plum nuts. I can get closer, but I will have to bring a chain saw and get to where I can get the hood up or get a door open. If this is factory, will it fit a 1/2 ton?? If I'm not seeing things, what do I need to look for. I did a search, but could not find any info. Thanks, Joe

Joe, I know for sure the 60-66 big trucks were available with automatics, but I can't say about the AD trucks. I know someone here can answer that. The ones in the 60-66 trucks were awful big to put in a 1/2 ton but I'm sure it could be done.

Thanks for the reply. I take it that the trans were different between 1/2-3/4-1ton trucks than on the larger trucks. If thats the case, I'd be barkin up the wrong tree. My problem is this, I have a factory early 55 auto trans cab, but when I bought the truck, the PO had sold the trans to a drag racer so I'm trying to get an auto to make the truck factory original. I know there are a lot of other parts and pieces that go along with the factory auto AD trucks, but I think I have just about everything except the trans and from what I've seen they are hard to find and even harder to get someone who knows how to rebuild one. especially for somebody like me who has to operate on the cheap. Joe

Joe, yes the 60-66 big truck automatics were definately different from the 1/2 & 3/4 ton transmissions. Most had no park gear and some even had a retarder brake. Again, I do not know about the AD trucks, but I would think that if they were available with an automatic it would most likely be bigger. I'm sure some of the AD experts here will know.

1954/55 Advance-Design Chevrolet trucks had an optional 4 speed Hydra-Matic transmission available on all 1/2, 3/4, and 1 ton models. The larger Chevrolet trucks did not have the Hydra-Matic option in 54/55.

Larger GMC New Design trucks (right up to the 950 series - 8 ton trucks?) had Hydra-Matic options by late 1955 but I am not sure if they were available in the Z-series (54/55) GMC trucks.

One of the late 1955 Hydra-Matic options was a Twin Hydra-Matic transmission ( . . . two four-speed transmissions mounted one above the other.) that had 7 forward gears. The Twin Hydra-Matic had optional 2-speed or 3-speed reduction units, resulting in either 14 or 21 forward gears.

Tim

There was an optional Factory Automatic transmission available for 1954 GMC 2 ton, & up trucks.

Thanks, Spanky.

The tranny could be the Allison 6 speed automatic, especially in the larger trucks. It probably will not work for your appilcation. Look inside the cab of the truck and see if you can see the shift tower or the retarder pedal on the floorboard.(where the clutch pedal usually goes). Any pics??
Thanks,
Byron

Joe, I think I can get my hands on a 54 or 55 1st.with a hydramatic - if you're interested. Joe Dial Canadian, Texas