Inliners International Forums General Discussion Drive Train 3 speed overdrive rebuild

Hi Steve here,

It has been a long time since I have posted any questions, or responded to any questions. The question I have today is if parts from a three speed overdrive can be added to another three speed. What I have is a 57 chevy 3 with overdrive that I had to pull out of my truck because the main case is leaking, it must have a fine crack in it. I have another case to swap it out. I just recently purchased a saganaw 3 speed out of a early 70's vehicle, at least that is what I was told it was bolted up to a 292 6 cylinder. That is the background information.

What I would like to know is if the overdrive parts can be taken off of the 57 tranny and added to the saganaw? or will that not work because of internal parts being different? I know the saganaw came out with a overdrive. the bolt patterns look to be the same on the trannies.

The reason I am asking is that I am finding that I like the saganaw because you can down shift into 1st gear and the 57 tranny you have to come to a complete stop before down shifting. I know I can tear them apart and compare the differences, to see if it might work but I don't want to wast time if it will not work. Plus there are so many others out there that have such experience and knowledge that I can learn from.

Thanks for the help, if anyone has any information about this I sure would appriciate it. I am hoping to take a road trip in my truck at the end of the summer and would like to have the overdrive back in the truck and working.

Thanks Steve

Here's a link that may help;

http://www.classictruckshop.com/clubs/earlyburbs/projects/how_to.htm

LG

Thanks for the link,

I looked and it's a great site, after looking it seems to me the specific question I should be asking is if the main shaft would be the same, where the overdrive bolts up? If it is it seems to me that the overdrive unit should work. I don't know if the tranny with overdrive main shaft is the same as one that is not an overdrive.

Thanks again Steve

Have you tried talking to a tranny shop?

I'd double check and make sure the leak is really a problem with the case, as your posting sounds like you are unsure?

Cat iron can be welded...

50's units are not the same as 60-70's units from what I've been told.

tailshaft spline counts are going to be different.

When converting a Saginaw 4spd to a 4spd with OD, they use an OD unit from the later 3spds, not the 50's vintage ones. So, with that in mind, I doubt that you could put the later parts into the earlier case??

Thanks LGriffin and Gearhead for the replys.

I know that the internals of the two trannies are different I just thought I would ask. I know it is the case that is leaking maybe I will look at having it welded as an option. The only way I will know for sure is when I tear the overdrive tranny apart I will take the rear section off the other tranny and check if it may be possible. As I am writing this I just remembered that I have a overdrive section that has the same tailshaft spline count that is the same as the saganaw. I was able to pick up a real good saganaw tranny for 20 dollars and one for 40 dollars at the last swap meet. I guess with all the other options out there now the three speed is not the tranny of choice. If I learn any positive results I wiil post what I learn.

Thanks Steve

No, the parts won't interchange between the old 57 muncie and the newer Saginaw. Sorry. Joe