Interchangeable parts on the 54-56 Cadillacs?

[64\/54Cadillacking]

Does anyone know what parts, mechanical, electrical and chassis wise will fit or can be modified to work on each year?

For instance what about the washer bottle, lid, bracket and assembly? Could I buy one off a 55-56, or is it a 54 only part?

Intake manifolds as well?

Thanks guys.

[fishnjim]

You can obtain an interchange manual for this period.   Some of your items are listed some are not.   For those unlisted, you have to refer to the parts list, and cross those part numbers.   Usually it'll say what years they cover.  Best to get one closest to your time period as they tend to obsolete and substitute with time.
They're easily available from auto lit companies, Fazon, Bishko, etc.   Just search.

[64\/54Cadillacking]

Thanks Jim,

I thought I might have to do that, but I wasn’t sure if the manual covered every single part in and on the car.

For instance i almost purchased a NOS Delco-Remy horn relay from a 55 Cadillac, but it won’t work on a 54, even though they are only a year apart. So many little changes from year to year on these 54-56 Cads that it’s crazy!

My 64 is kinda like this too (same can be said of the 63’s), it’s probably a bit worse on the 64 because of the 1 year only Parts such as the front end grill, and rear end assembly treatment,  comfort automatic climate control, the first year of the Turbo400 trans that used a special adapter plate in order for the engine to receive the new transmission. As well as the introduction of the 429 that made a lot of internal changes to the inside of the motor that is also 64 only.

For instance my 64 has a 67 engine block, but with 64 heads and intake. The water pump is from a 67, the fuel pump is 67 only, and my transmission is from a 65!! But it somehow all works together.

The hardest part of restoring a car is not necessarily getting it to look nice and pretty, but figuring out what you can use from other years of cars that can fit and work on another year without any trouble at all. This can save one a lot of time searching for parts that you thought you couldn’t use at first, but actually could. And it can definitely speed up the restoration process.

[Lexi]

Agree with fishnjim to get some interchange reference literature. The Hollander Interchange Manual, (26th ed) is a nice item to have, and it would cover those years of Cadillac where there would be much cross over in your case. Not all is noted, so the Cadillac MPL is also required but a few items are not even listed there, and others are grouped together, (hence hidden). It often doesn't offer you any way to positively identify parts that are not in a box with the original GM part number.

Examples: you mentioned the washer bottle. The MPL lists 1950 - 1958 as the same for Cadillac. Dimensions are not stated, (& no pictures in the one I checked), and Trico made different sizes back in the day. GM used lots of them as well as others. I believe Fusick lists dimensions for the repops. But if you don't have one to compare, or yours is wrong, and there are no pictures or dimensions given, searching for the correct part can still be a challenge even with the above noted manuals. What about what's inside your oil filter canister? They are listed but if I recall correctly some of the inside parts are not. It was sold as a set so not everything was listed individually. Looking for a jack to complete the restoration of your trunk? They too are listed, BUT, again no pictures. And there are some peripheral items associated with them that you will need as well.

So reading the MPL is sometimes a little like decoding Egyptian Hieroglyphics. Figuring out exactly what it is telling you can sometimes be daunting. Then there are parts that have different part numbers BUT they will still fit your car! At times a minor modification has to be made, or there is simply an extra bracket or mounting hole that is not needed on your car, or you by-pass another unused fitting, (some neutral safety switches for example). Finally, the MPL won't usually help you when out at a swap meet and you are digging through scads of odds and ends. Nothing beats a well preserved reference car. Clay/Lexi

[64\/54Cadillacking]

So true Lexi. It’s nice to have a interchange manual, but what if one goes to a swap meet for car parts, and there’s no part number on the part itself to verify if the part will fit or not.

So even with a manual, not every part is covered. Especially body parts and trim.


Thanks Lexi.

[Lexi]

Yes, that is the problem. I see the various manuals as parts of the bigger picture which is like a puzzle. They really come in handy sometimes and are a useful adjunct to your research. Occasionally some parts actually have the MPL number on them. You mentioned intake manifolds in your first post. The intake manifold on my '56 (and other years such as 1959 for example), have the part number cast into it topside. That makes it easy...in that case...

But consider bumper jacks which I mentioned earlier. I needed one for my '56 Series 75, as mine was missing. Under a 1961 MPL with an updated 1962 page attached, section 3.0488 says (quote) "1949 - 1962-75, CC sill jack, with handle".  So I thought I would have to look for a sill jack for my car. Made sense as a Limo is a heavy car and the commercial chassis cars also were noted for such. Good luck finding one of those right? But the next section, 3.0489 says (quote) "Handle, Auto Jack 1948 - 1958-75 For Bumper Jack". WTF?

Other oddities also appear on that page. Of course there are no pictures. I won't go into the lengthy chit chat that took place on the old Mid-Century Cadillac forum, but reading this I and other members were confused as to whether the Series 75 came with a "sill jack" or a bumper jack or both or there was an error. The 1956 MPL was actually more clear. I believe it was Roger Zimmermann who in the final analysis was of the opinion that I needed a bumper jack. I got to check one reference car which I believe was all original at a Grand National. It was a bumper jack. No thanks to the MPL! Also, the infamous and dodgy (hard to find) single year (1956) jack hold down clip is there, BUT there are no pictures and of course no part # is to be found on an item that small. Without having seen one for comparison purposes, imagine trying to pick one out of a rusty parts heap at Hershey? Nope.

I mention these as examples of the ambiguity as well as other problems that come with using some parts of the MPL (as well as some editions). That is why I own several; 1) one for my year of car as it should be the most complete and 2) A later edition which hopefully captures any changes and fixes errors, (though they usually start cutting down on the quantity of info as the model year becomes more obsolete). I came away having even greater respect for all auto parts guys who have to read and interpret these parts manuals. You just really got to research all and talk to people, examine reference cars as well as handle the parts. Clay/Lexi