I have a chance to pick up an old GM Hyramatic trans and eng from a 55 GMC p/u. (4 spd) Would this be the same trans that was so popular in drag racing back in the day? And if so, what would one need to make it work today? I recall some were called "clutch-turbos" or was that something different? I thought maybe somebody here would clue me in on these.....I would love to have one behind the '09 thanks
It's basically the same trans as the B&M hydro-sticks were built from. A clutch flight or clutch turbohydramatic are a bit different. They use manual clutches ahead of an automatic trans instead of a torque converter and were built for racing applications and, in my opinion, that is their only practical use. Your Hydra-magic would be fine for the street. Not as efficient as modern automatics, but a nice nostalgia piece and a blast to listen to as they upshift on acceleration. Ray
The truck transmissions had lower first gear. What do you plan on putting it in? If the GMC truck was a V-8 truck, then it had a Pontiac engine, and would have the Pontiac bellhousing. The transmission itself can be bolted to any bellhousing meant for a hydramatic, Chevrolet, Oldsmobile, Nash, etc. If you plan on a Chevrolet, you might just want to start with a complete unit from a Chevrolet truck; some of the pieces, such as slip yoke and starter motor are almost impossible to find by themselves. Butch/56sedandelivery.
If you can score the OEM column with shifter and linkages, they are rare and hard to come by these days.
The 55 hydramatic is one of the stronger units, and might even be a "slant pan" unit. I have a 55 Pontiac 287 and the hydro that came with it and the trans is a slant pan. When you say '09 what are you referring to? 409, or a 2009 car/truck?
The truck version you have is called a flat pan. Another nice feature of the truck hydro is that it has a 10" torus as opposed to the car version 11". Gives you a little more stall.
Is the 10" torus and flat pan correct for a GMC truck with Pontiac engine? I know the Chevy hydro has what you call out, but wonder about the GMC truck version.
To start with a clutch turbo is a turbo 350 or 400 with a clutch in place of the torque converter. What it takes for the slant pan you have is to be full of fluid and put it in gear and drive it. Make sure that you have all the original linkeage and that your throttle position linkeage is properly adjusted. Unless it is wore out in which case you have to take that big ol heavy pig to someone who can rebuild it for you.
Good info guys, thanks. Keep it coming. As to what I meant by '09.....A '53 Chev with g***er type with a dual quad 409.. It was going to be a T-10, but at my age, and with my knees, an auto would be good. A "Hydro-stick" is what I was dreaming about instead of the clutch-turbo. It is still in whats left of the truck, so everythiing is still there. It has a 6 cyl in it. My Dad had one of these when I was 17 and it may be the same truck.
The GMC truck, as was pointed out came with a 287 Pontiac engine, which definitely has a bell pattern of it's own. So you might be able to use the actual box, but you will need the Chevy flywheel, torus cover, torus members, check valve, and the unusual starter. Finding these items may be very hard and very costly. I am not trying change your mind (I am one of the great hydro fans out there), but in your case you might be better off with a more modern transmission such as TH400, 700R4, 2004R, 4L80.
In order to run a Hydro with a 409, you'll need the Chevrolet flywheel/bellhousing/torus ***embly, AND, the flywheel will need to be machined for clearance of the small counterweight at the crank flange. The various companies that used to market the Hydro's did this routinely so the trans could be used behind more than just the 265 or 283 engines the hydro's came behind, and those engines had a round crank flange with no balance weight. I still say to look for a complete Chevrolet truck hydro, and get the 53 GMC trans for parts and such. The Hydro also came as a Clutch Hydro; there was one here in the cl***ifieds some time back, but it's no longer there. Only one I've ever seen. Butch/56sedandelivery.
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