Packard Forum Index » Post-War (1946-54)

they seem like an auto swap is the only option is there is any difference in the crank from stick to auto? can I swap a 1948 motor to a 1951 auto trans?

Are you talking about putting a '48 motor into a '51 car? If so, then no, it won't work unless you build motor mounts. The '50 and earlier cars had a front engine mount off of the timing cover plate. The '51-'54 cars had the motor mounts cast into the side of the block. You can put a '51-'54 engine into the '50 and earlier cars, just use the earlier mounting. But ya can't go the other way.

As for transmission swapping, as long as you get the bellhousing and flexplate off of the donor car you're getting the trans out of, you should have no problems physically bolting the engine up to the trans. Also, if I were you, I'd disregard the use of the stock trans cooler, and get you an aftermarket one that's heavy duty, you're trans will love you for it. If you were close, I could help you do this swap, it isn't hard to do, and I plan on going the other way (auto to stick) pretty soon.

Believe this started with you and a 47 and not sure exactly what you're wanting to swap or which engine you have. There is an article on later engine swaps to postwar cars with 356 engines in 1953 SC Vol 27 #7 detailing what you need and mods. That only covers the engine so you'd be on your own to figure out trans mount, linkage etc. Suppose you could install eng trans as a unit but you'd still have to figure out how to hold up the back end because I think the frames are a bit different in that area also. Available on website here.https://packardinfo.com/xoops/html/modules/article/view.article.php?81

Edit: The URL to articles seems to have been truncated. It is item 14 under service bulletins in case it doesn't work for you.

G'day all, I converted a 48 manual to a Ultra in the Seventies and it required an auto steering column and linkages, a flex plate instead of a flywheel, also had to machine the back of the crank to take the converter hub ( we did not disasssemle the motor to bore out the crank). It was very successful. However, knowing what I know now, I would not do it, as a R11 o'd is so much more flexible and economical than an Ultramatic. I would recommend the R11. Best regards Peter Toet

Dear BDK:

The key phrase here is "good customer".

Coverting to automatic is very expensive and unless they insist on keeping that car you could probably do better by finding them a trade.

That way you would get the new work on the next car, which is safer than this one time conversion. The first one always takes twice as long and in this case you don't get anymore of this type of job. You will probably lose money on the job.

After the trade the power steering issue depends on whether the tie rods are inter-changable. I don't know.

The customer is not always right. However, if they are a customer you value you try to keep the business. There are a lot of people you don't want as customers.