The Stovebolt Site Forums The Shop Area Engine Shop overdrive transmissions

Last week at the swap meet in Arlington, TX, there were many OD transmissions. They ranged from $75 to $450. Big difference.

On some of them I pulled off the side cover and most of them had chipped gears and the 'planitary gear.'

How can I tell if the transmission is worth buying?

I met a fellow who said he had 2 transmissions that were together and 1 taken apart. I was planning on going out to look at them but was unsure on what to look at or to check.

Any help or suggestions?

TIA

Oldblue, if you're talking about removing the 4 bolt side cover on an old Muncie tranmission with a Warner OD, you are looking at the 1st-reverse sliding gear.Normally the one side of the large sliding gear is chipped from grinding into first when moving, no big deal, you can even turn the gear arounf 180 degrees. To access the OD gearset, you need to pull the tailhousing.

i was given two three speed with overdrive transmissions,but i don't know how to id them.anyone know a website?

I'm in the process of making one good transmission out of the parts of three, all from the '55-'62 era. I was popping out of 3rd gear at speed, a little too hairy @65-70 mph. I'm digging the 3-on-the-tree, few people know how to drive one. I set up an overdrive on/off switch complete w/ idiot light (starting off in overdrive is a no no) in the throttle hole with the 'T' knob and can split the gears and get a six speed out of it. Sounds complicated but isn't. Just purchased a bearings (all three) and small parts kit for this model 3sp+od from a trans firm in Portland OR, good price, complete kit w/ gaskets included. Advice, hmmm. Have it rebuilt by a reputible firm and it will last you forever. If you do it the way I have it will take you longer but it is The Road Less Travelled (all credit to Robert Frost). I have period literature on the OD but it could have been better written. How many guys got A's in Auto Shop AND English in High School? Email me if you need help. If you think we can help others we'll clean it up and bring it back to the board as a Tech Tip. PS the .70 OD X my 3.90 rear gives me a final drive of 2.73, it's great man.

Tony,

yes, I was taking off the side cover and the big gear (1st-reverse?) was somewhat chipped, along with the other gear that was perpendicular (planitary?). And it wasn't too bad. So if these gears are chipped (and how bad?) that is no problem?

Another fellow that reworked the transmissions - and sold them guaranteed for $450 - said to check the overdrive part you need to put it in gear (2 or 3rd) and hold onto the output shaft and turn the input shaft. If the shafts turn the opposite direction then the transmission was good. All the ones I tried did this. Is this true?

I thought the major component of these was the electric parts. There seem to be two. A solinoid and the governor. From past posts I think the governor can be plugged but the solinoid is hard to find. Is this true? Can they be checked with a battery and cables?

Thanks again.

Old Blue, perpendicular? all the gears in the main case are on the same axis.Besides the big gear, the lower cluster gear may show chips from contact with the slider. A small amount of damage is ok for an old tranny but it is a judgement call.I am not the best guy to ask about these overunning clutch overdrive units, Perhaps Cosmo knows. But I do know replacement parts can be difficult to find

Cosmo
I run a 3 speed in my 57 stepside, it needs a little work and would be interested in seeing the period literature you have, as well as others I am sure would.

Willy 57

Yes, the solonoid can be checked with hot from a 12 volt battery, it's job is to sustain the out position. You could unbolt it from the housing being careful to 'turn the key' a few degrees to release it, it won't pull out directly. I don't want anyone upset with me for copyright infringement, so I would send information re: the OD person to person. From my limited experience, it's the 3 speed part of the 3sp+od that goes awry, such as the 2-3 synchro and it's ring gear. I did mention a rebuild kit I bought recently, for 50 bucks you can't go wrong; ALL 3 main bearings, ALL the needle bearings, NEW snap rings, small parts, and a complete gasket kit. They also include a diagram that will help you with your takeapart and rebuild. Email me for this vendor, I don't know if mentioning the firm is Kosher. Oh, if you're going to do a rebuild (this is going to sound nuts) save one or two of those wide broccoli rubber bands, you'll need one for slipping the OD housing back on, that's one thing the literature doesn't tell you. The rubber band disintegrates in the 90 weight and will do no harm to your tranny.

For those interested in the three speed w/OD you could benefit from checking these links out, I am certain. wiring rebuild

It seems to me that there used to be a writeup about mating one of these sag overdrives to a four speed anybody seen that?

Yeah bzn, I have the article somewhere around here. it was from car craft magazine I think.Basically you strip the main shafts and swap the gears , drill a hole in the 4 speed housing and weld a piece of flat stock on the reverse rod to keep it from engaging O/D when in rev.It was a very detailed article except for the part about welding the flat stock on the shifter arm. Left me a little puzzled, I have both the late saginaw 3sp wO/D and the 4sp saginaw and would like to do this.

The article is at Chevytrucks ...not credited but from the October 1975 Hot Rod Magazine. The reverse tab is a little tricky to get positioned exactly right. I took a spare side cover and cut off part of it so I could watch how the shifter pawls operate. Got it pretty close that way, but this is a trial and error deal. All this tab does is actuate the mechanical OD lockout when reverse is engaged, so if you always remember to lock out the OD via the cable before trying to get reverse, you accomplish the same thing. But if you accidentally engage the solenoid while in reverse, no telling what could get hosed up. It's safer to take the extra effort and be sure. A couple of other things, not mentioned in the article, are to drill and tap the main Saginaw case for a drain plug while you have it stripped down. It's also handy to drill through a hole through both mounting flanges so that the tranny and OD share the same lubricant. Saves having to fill them separately

Thanks Jack--I knew I'd seen it somwheres!