3 speed overdrive rebuild questions
 

Looking at getting a three speed manual with overdrive out of a 55-56-57 car. Has been sitting for a while with no side cover on the case, seller says it will probably need to be soaked for a while and the gears freed up. How hard is it going to be to get parts to rebuild this? Anything on the overdrive unit that can go bad, or any way to check that it's good? What's a good price on a mystery trans that's been sitting?

Thanks!

Re: 3 speed overdrive rebuild questions
 

If it's a stick shift trans, and a mystery, $100-150. I got my first np440 for $150 from a guy who thought it was a "granny low side loader 4 spd" (????) I would have paid double that for it.

Re: 3 speed overdrive rebuild questions
 

Thanks for the direction, that makes me feel a little better about it. Where do folks get parts for these olds transmissions?

Re: 3 speed overdrive rebuild questions
 

Any ideas on where to get rebuild parts?

Re: 3 speed overdrive rebuild questions
 

if its all rusty inside i would ask him to give it to ya. reg 3sp main gears will interchange if i remember right. the O/D main case is different (has a hole for a rod out of the O/D) i thank it keeps the trans from going into reverse while in O/D. so if the O/D unit is ok you should be able to find parts maybe for the main trans. O/D hard parts, i haven't a clue. I ran these trans in a couple of trucks about 30+ years ago. it would have to be cheap for me to buy. a 5 speed would be much better.

Re: 3 speed overdrive rebuild questions
 

Thanks 61K10. I agree that a 5 speed would be a no brainer; however, right now I would like to retain the 3 speed on the column for originality's sake and to keep from having to cut up my floor as much as possible. Maybe one day though...:metal:

Re: 3 speed overdrive rebuild questions
 

JC-----call some trans shops that rebuild manual trans---take some pics of the trans and post them.

Re: 3 speed overdrive rebuild questions
 

Yea I think I will call around and see what the shops say. The transmissions are a good four hours from where I live now but they are a lot closer to my dad so he is going to pick them up for me this weekend. I'll get some pics up when I get them. I'm getting two of the transmissions in the deal for a price I didn't mind taking a gamble on them for so we will see what happens.

Fingers crossed...

Re: 3 speed overdrive rebuild questions
 

JC---there is some rebuild kits out there--all bearings and gaskets/seal, just hard parts--gears/shafts/sync row drum etc are harder to find. with 2 trans you should be able to make one good one. there are pretty easy to work on------good luck

Re: 3 speed overdrive rebuild questions
 

^ I agree.

Here is a bearing/gasket/seal kit for the 319 ... the overdrive version of the 318 3-speed with the 4-bolt side cover: http://www.ebay.com/itm/GMC-Chevy-Mu...item27b462295b

Dad was in a similar situation a few years ago. He found 3-speed OD trans that was a bit rusty inside. He started checking around for a non-OD trans to use as a gears/parts donor when he stumbled across another 3-speed OD trans that was almost like new inside and less expensive than the rusty one. I'm sure he probably just got lucky on that find, but it wouldn't hurt to look around some more before buying the rusty one.

Like 61K10 said earlier, you can use a non-OD donor 3-speed for the parts that aren't OD specific. So the biggest concern with rust would be with the OD parts like the planetary gear set, one-way roller clutch, etc. If those parts are rusted beyond use you're better off looking for a different transmission to start with. Also check the condition of the solenoid that engages the overdrive (it should make a fairly loud clunk when you ground the case and apply power to the larger of the two screw terminals). Those solenoids can be pricey if it needs to be replaced.

Re: 3 speed overdrive rebuild questions
 

If the gears and everything are heavily rusted, you have a display piece. Bearings and such can be replaced but rusted gears usually don't last long even cleaned up real nice.

Re: 3 speed overdrive rebuild questions
 

Thanks for all the tips guys! Good info on checking out the solenoid. The old man selling them says the rust is only minor so we will see. I do have a good three speed in my truck at the moment so if worse comes to worse I think I could swap out the gears.

Re: 3 speed overdrive rebuild questions
 

JC--now don't forget the pic's

Re: 3 speed overdrive rebuild questions
 

Don't worry brother, I won't leave ya hangin! I'll get my dad or brother to send me a couple of teasers on Saturday. Looking forward to this project! Now if only I could get my c-notch finished and my bed put back on!

Re: 3 speed overdrive rebuild questions
 

Got a couple pics from my brother yesterday. One trans is a little better shape than the other, but both should be serviceable transmissions. My dad said he was pretty pleasantly surprised when he picked them up for me. I think we both were expecting them to look like the spent their lives submerged on the ocean floor!

Re: 3 speed overdrive rebuild questions
 

This guy has parts for my 3 speed overdrive in pa.

Re: 3 speed overdrive rebuild questions
 

Excellent, thanks!

Re: 3 speed overdrive rebuild questions
 

that rod is to lock out the overdrive when you are in reverse if it does not lock out you dont back up (overrunning clutch)

Re: 3 speed overdrive rebuild questions
 

Got the transmissions in my possession now. heres a couple pics. my dad gave me an extra three speed he had so I've got a good side cover and gears if I end up needing them.

Re: 3 speed overdrive rebuild questions
 

Ive got an extra mc318 up here in NC if you find yourself needing gears.

Re: 3 speed overdrive rebuild questions
 

thanks! hopefully between the extra one from my dad and my current trans I will have a decent set :lol:

Re: 3 speed overdrive rebuild questions
 

I think I would like to find one for my truck. I am kinda liking the 3 on the tree and am thinking about keeping it. I was going to put a 700R4 in, but have some doughts about that now.