transmission install issues on 54 vs 56

[Guest kevinshea]

I recently installed the transmission on my 54. When I got the car it had a 56 transmission in it, which, by the way, is about 1/2" longer than the 54 tranny. I got the 54 rebuilt and put in in place, mounted the engine and found the engine mounts off by about 1/2". I was concerned but not overly. I considered getting out the engine stretcher, but realized that if the car was modified to fit the 56, what else changed? I opened the parts book and noted that the 54/55 transmission cross member was a different part# than the 56. I had a donor car, and picked the 54 cross member off it. The differences are shown in the image. The 54 is bent forward some, while the 56 is straight. Also shown are the shims. The single one is for side to side shimming of the cross member, and the others are to shim the thrust mount. I really didn't understand how the thrust shims help, since the mount installation was rather tight. I am curious if someone really understands what these shims were used to compensate for.

[old-tank]

Kevin

Thanks for sharing the difference with the transmission cross member...learned something today.

On the shims I leave them out unless there is a space to install them easily.

Willie