The Stovebolt Site Forums The Shop Area Engine Shop Overdrive Transmissions

I have a 56 pick up truck all stock with a standard 3 speed transmission. I'm looking to install a 57 3 speed with overdrive. Does this work? How much trouble will it be? Will it let me drive at 60-65MPH? Is $100.00 a fair price for the transmission? Any comments will be appreciated.
thanks.

is that a 3-speed column?

Yes it works. They were an original option. They have a governer and a solinoid that kicks them in. You can also manually switch them with a kit that is available. It will let you go 60-65 without working the engine too hard. You can also get a different gearset for the rear end, but the OD gives you more speeds and more flexibility. You'll still have a good low gear with it. The shifter is not an issue that I know of whether its column or floor.

100 is cheeeep if it's in decent condition - direct bolt in replacement for what ya got now - same trans as was available 55 to the mid/late 60's

Bill

Many thanks for the reply's. It is a column shift, but that appears not to be a problem. It sounds like a "kit" is available to make this all work. Can anyone tell me where I might find such a thing?

Thanks for the reply's. My truck is a column shift which doesn't seem to be a problem. Sounds like this may be the answer I am looking for. Where is the best place to get the additional parts I will need? I live in So. Ca.

I really think you should buy it for $100 and then immediately sell it to me for $150. :rolleyes:

my 67 chevelle has a 3 speed with overdrive under the dash but it wont engage if you use it when you let off the gas it free wheels but i think it is suppose to shift it to a higher gearing but it dosent do it

My '55 did that. It turned out to be a broken
rear bearing retainer clip. The piece lodged in
the blocker ring. Ended up buying another trans
to scavenge the parts to fix it.
Oh, and $100-150 seems to be the average rate for
an overdrive 3-speed at the swap meets I go to,
mainly in the Indianapolis area.

oldschool, what "additional parts"? the linkage and the column parts are the same - if you need the carb mounted kick down switch and underdash cable control, they should come w/ the trans or you'll have to fake it, new parts not available, and if it doesn't have a good solenoid already mounted on it, pass it up!

Bill

Overdrive inc. has a manual solenoid conversion
that is cable actuated. A pto control cable works
better for the freewheel control than a standard
bowden cable, it is much stonger. I used one for
a Chelsea unit on mine, I think it was about $35
at my local parts store.

how do i get in touch with overdrive inc?

Those old Borgwarner OD's are 30% so going 70mph with one would have your engine turning the same rpm as it does now at 49mph. One of the above replies gave good advice on the solenoid, if it doesn't have one or it doesn't work, finding one is hard and will cost as much as a the trans.

Gentlemen, doing a search for info on three speed od transmissions, I came across this thread. I want to install one in my 56 but have a couple of questions. Does the driveshaft need to be modified (shortened)? Does anybody have pics of what the carb mounted kick down switch looks like and the underdash cable control? Does the overdrive kick in automatically, or do you "switch it on" when you get on the highway? Thanks!

RichN you can get all the info needed for these transmissions at www.classictruckshop.com/earlyburbs/projects/t85n/rebuild.htm I downloaded a 5 page sheet from this sight 7/7/05 and it outlines everything. Good luck.
Tom

Sorry but no pics to send you. I have 3-spd OD behind 261 in my '56. The kick-down switch must have always on/always off connections. I stacked two small switches together and manufactured the rest and attached the unit off of one bolt on carb. Unfortunately, when completed it did not work because of an internal problem in my solenoid. An additional problem is that my trans had the wrong governor (a simple unit screwed into the side of the trans that spins around and makes and breaks electrical contact to tell the trans it's ok to be in overdrive (approx. 27 mph) or that you are going too slow so go to free wheel. As a result, I have to switch it manually. I just put in a switch and a reminder light (reminds me to take it out of OD when going too slow or stopping). It works well and also allows me to kick down manually by just hitting the switch so even though I have no kick down or governor, I still get the benefit of OD. It just isn't a "no-brainer" process. Your best bet for understanding the whole process may be to to get a shop manual if you don't have one and look at the simplified electrical drawing. By the way, I did have to shorten my drive shaft. The cable I got with my tranny was toast so I used a cable I got from a truck supply company. Any cable with a T-handle will work to lock the tranny out of free-wheel/OD mode. Hope this helps.

The Central Oklahoma Classic Chevy Club has online assembly manuals for the 55-57 passenger cars. You have to go to their main page and choose reference section, then 1955-57 Assembly manuals, pick the manual you need and then scroll down to the section on Transmission Overdrive. You'll find diagrams of the control, the harness and relay, a wiring diagram and the kickdown switch for both the 6cyl and 8 cyl engines.
I'm not sure how much this differs from the trucks but it may help.

http://www.55-57chevys.com/coccc/index2.html

I have a 7 bolt side cover saginal full sinco 3 speed complete plus a complete od tail for it if someone is intrusted. they are better than the the 4 bolt side covers