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#46770 06/23/2005 5:04 PM | Joined: May 2005 Posts: 86 'Bolter | | 'Bolter Joined: May 2005 Posts: 86 | Is the driveline for a 1/2 ton Chevy AD pickup the same for both the 3 speed column and 4 speed floor transmission.
In other words, is it a straight changeout to replace one for another.
Mike
1951 Chevy 1/2 ton w/ 1959 235
1971 Chevelle
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#46771 06/23/2005 7:14 PM | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | Someone correct me if I'm wrong...
First is that there were at least two, maybe three different 3-speeds used '47 to '55 1st.
Second, '47 to '54 all have the closed driveline, while '55 1st (all '55 ADs) have an open driveline.
Third, there is one more transmission option in the mix, which is the Hydromatic.
I believe, and this is where I'm a little uncertain, that each transmission option means a different drive shaft and torque tube (where relevant).
Most of this is information I've picked up here, so if I've gotten any of it wrong, please someone correct me...
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble... | | |
#46772 06/23/2005 7:32 PM | Joined: Jan 2001 Posts: 428 Shop Shark | | Shop Shark Joined: Jan 2001 Posts: 428 | According to my parts book, there were 3 different depending on year. One is listed for 1947 only, which was the last year for the old style tranny. One listed for 48-50, same part for either 3 or 4 speed. And one listed for 51-up. I believe the only difference between the 48-50 unit and the 51 and later was a change in the torque tube bushings, but I'm not 100%.
If your's is a 48-54, you would be able to swap a 48-54 1/2 ton 4 speed for a 3 speed,or vice-versa. The tranny must be from a 1/2 ton and you must use the corresponding u-joint for the tranny.
Bob | | |
#46773 06/23/2005 11:05 PM | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | Bob I'm sure I've read somewhere that the Hydromatic trucks used a different torque tube. Is that incorrect?
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble... | | |
#46774 06/24/2005 1:48 AM | Joined: Mar 2005 Posts: 637 Shop Shark | | Shop Shark Joined: Mar 2005 Posts: 637 | I have changed an automatic (P.G.) for a 3 speed in a '52 it was a direct replacement with no change to the drive shaft so the two transmissions are the same length. | | |
#46775 06/24/2005 2:01 AM | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | OldSub,
Yes, the torque tube for the 1/2 ton 1954 Hydra-Matic has a shorter length due to the longer length of the transmission.
The standard 3-speed, the heavy duty 3-speed, and the 4-speed transmissions are all the same length.
Tim | | |
#46776 06/27/2005 1:37 AM | Joined: Jun 2005 Posts: 1 Junior Member | | Junior Member Joined: Jun 2005 Posts: 1 | where can i get a hydramatic for my 1954 chevy truck? please advise someone. thanks, doug carter, haynesville, la. 318-245-1150 | | |
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