The Stovebolt Site Forums The Shop Area Engine Shop 54 Chevy Hydramatic research

I have a 54 3100 that currently has 3 speed column shift. I have located a 54 Hydramatic driveline that includes engine, tranny, rear end, and frame. Have not taken delivery of it yet but have been told that shift indicator is with it but linkage may have disappeared. I want to make as correct and complete a swap as possible but in all honesty have not even seen a Hydramatic truck yet. Have researched this site for parts that are proprietary to the auto but would appreciate any help, info, or leads on parts I may need for change over. Any pics would be great and would like to tap into any expertise available. Thanks in advance. Greg H.

Greg - what ya need is the assembly manual, which will have pics of every nut n bolt required for the hydro and if same or different from 3 or 4 spd - have you noticed any place around for parts [like rebuild kit] for those trannies? might wind up w/ something that's not repairable if it breaks, which might be why you never see'em around

Bill

Last year I contacted a place in ohio near cleveland that dealt in 47 and up chevy and gmc trucks that had a 55.1 that still had the hydromatic in it,I was considering installing the trans and rear in my 37 but I found out the rear was too wide and gave up on that idea. I think it was bobs chevy trucks and I dont have their email address any more but should be to be found.

To do it right you'll have to replace the floor pan with one from a hydramatic truck. You'll have to cut out some of your firewall. I'm assuming it's like the '54 GMC.

I have the assy. manual and from what I could tell, the floor pan was the same. It appears that there is a cover that covers floor starter hole. Assume that tranny cover should have an extra hole to check and fill tranny fluid. I would love to see detail photos of trucks that someone might have that show items of interest. Even pics showing starter switch and shift indicator, neutral safety switch, Extra hole covers and pedal arrangments would be greatly appreciated. Thanks again G.H.

Hi Greg,

Someone recommended that you research the overhaul parts for the transmission. I had a 54 GMC many years ago with an hydromatic tranny and it was a factory four speed (which was the same as the cadillac four speed tranny). I rebuilt a 56 cadillac transmission in 1962 and found that the piston seals were metal (like large piston rings) and with the piston action, they wore the inside of the clutch hubs. A complete rebuild with the replacement of the hubs was very expensive. You might want to see if you are getting this model transmission. Just letting you know what could be.

Truck Tinker from Talking Rock

Thanks for info on books and all. I was told tht entire driveline was running well not all that long ago. I have also bookmarked a site or 2 that deal with parts for those trannies. I guess I am remaining optimistic on this project until I shoot myself in the foot. I always learn more from my mistakes... If I do something right, It is usually just dumb luck! Thanks for all the help and if anyone runs across pics that might help, I appreciated being steered in the right direction. Again Thanks...G.H.

Wow, who would want a transmission that requires a 7 book series to explain how to service it. To me those things are like voodoo inside.

all ya gotta do is keep all the 3spd stuff in the corner so when the hydro goes south you can stuff it back in!

Bill

Greg H,

The transmission cover and hole are different. On the cover is the pivot for the gas pedal.

If you searched this forum, you found many comments about differences between manual and HydraMatic trucks. Here is one excerpt:

"Be sure you get the shift linkage, push button from the dash (to engage the special starter), starter with solenoid, frame crossbar (to support the rear of the transmission), the accelerator pedal and transmission cover for the cab floor. Also, be sure to get the shift indicator that goes on the steering column (it is cute and it is rare) and check to see if the mounting holes for the indicater are different than for a 3-speed (if they are, get the steering column). The brake master cylinder is unique to the1/2 ton Hydramatic and my Factory Assemblty Manual shows that the brake lines are routed differently."

Also, Mechainiac once posted this link as a possible source of parts: http://www.autotran.us/hmparts1.html

Here is another possible source: http://www.bright.net/~nrthwest/

Good luck to you. Please keep us informed of the progress of your project. As soon as I find a Hydramatic frame and cab (pipedream?), I will take on the same project (I have a drivetrain and all associated parts).

Tim

OK Greg, I took some pictures of the GMCs today. Like I said earlier, I'm assuming the Chevys are the same. Have a look at differences.

I hope this helps with your decision. I'm going with a TH200-4R myself.

Thank You! That is exactly the kind of help I was hoping for. G.H.

Ok now the question is... Are the Chevies and GMC covers the same? I asked the guy that had the truck that I will be getting driveline from and he does not recall that the accel. pedal was attatched to the floor trans cover. Have a GMC cover located but am working on a Chev. Thanks again, G.H.