1953 Transmission Swap

[Jim Black #21089]

Has any body installed a later model hydramatic or other more modern transmission in a 1953? Still having trouble getting mine to downshift. Thanks

[art woody]

The pre-55 331 c.i. motors are cast with a ledge, if you will at the rear of the block making any type of adaptor impracticle. However, if your pockets are deep enough you may contact Mid-Cal Transmissions @ 559-635-7589 for a custom built cadillac 400 turbo to fit early 331 engines. Included ( for a mere $3500) machining of your flywheel. Also you must lengthen your driveshaft 3 in. They will advise you on linkage setup and so-on. But check a manual first to make sure your linkage adjustments are correct on your hydromatic. I fixed mine by trial & error, works great. That 400 turbo is almost worth the aggravation it would save in the long haul.

[Doug Houston]

Id be the last one to say ANYTHING disparging about the THM400 transmission. Its one of the best transmissions that was made in the declining days of the american automobile. Ive driven a couple of hem over 200K miles, wihout problem.

But, the pre-1956 Hydra-Matic was also an outstanding masterpiece in its own right. With good seals and proper adjustments, the action of the shifts through takeoff is absolutely impressive. Ive installed postwar transmissions in my three 41 Cadillacs, and my 41 Oldsmobile. I rebuilt all of them myself, so I know just whats in them, and their operation is very gratifying.

I would hope that your transmission has been rebuilt by a competent  (and trustworthy) shop. That being done, adjustment by the shop manual will get you the most gratifying transmission you could ever want. So many of our fellow car nuts like to just Send it out and have it done. Most of the modern transmission shops have no clue as to what to do with a transmission thats over 50 years old. the result is always owner dissatisfation.

One of our CCCA guys locally has a 47 Cadillac and the H-M transmission was leaking. I tried to give him the name of a good guy in this area, but some hotshot sort of shoved me aside and gave him the number of some shop. The leaks were fixed.....sort of. The shop told him that all of those transmissions leak. Thats the way you tell if they have oil in them!!!!

I did mine, Im not in the transmission business, and they dont leak!

 

[Porter 21919]

Too often everyone wants to upgrade to some newer component, as if it will be better, even with all the inherent problems of modification upgrading.

Unfortunately finding a competent mechanic to repair an old car can be quite a challenge.

Any good mechanic will restore anything to as new, given the proper information to work with.

Ed Mobley rebuilt his Jetaway tranny on his 60 CDV, had to remove it once afterwards, to replace a component, typical from what he told me, a cracked aluminum housing, front pump, whatever.

Regards,

Porter

[Jim Black #21089]

Thanks for the advice. I can only get mine to downshift one gear and only at a very slow speed. When I am going up a hill, it will not down shift to a lower gear unless I almost stop. Is there any other adjustments other than the rod from the carb to the trans? Thanks in advance, Jim Black