65 3 on the tree with over drive ?'s

[j_lee223]

First thanks fellow gear heads for taking the time to me out. I’m trying to find a trany with an overdrive but I want to keep a three on the tree. If anyone knows of any trany out there that would bolt on and use the same linkage or if I can add and OD??? I want to keep the three on the tree because it holds sentimental value and I want to keep it a stock looking truck. What would my options be would i have to change my shift linkage?

Thanks again for your time.



Jusitn TX. CA.
USMC

[aerotruk63]

You could get a 3 speed with overdrive in this series truck.

[j_lee223]

Originally Posted by aerotruk63

You could get a 3 speed with overdrive in this series truck.

Great luck, do you know what trany that is or if that OD can bolf to my stock 3spd thanks

[luvbowties]

Originally Posted by j_lee223

Great luck, do you know what trany that is or if that OD can bolf to my stock 3spd thanks

Lee, GM's overdrives are complete transmissions not add-on-to-the-end units. Any overdrive from 1955 thru approx. 1969 should be roughly a bolt-in for your truck. (Among these, the earlier were non-synchronized in 1st gear, just like your orig. trans. The latter-year ones were fully-synch'd.)

I've used std. 3-speed floor-shifters and they fit the o/d trannies just like the non-overdrives. I feel sure one would conform to your stock, on the column shifter--maybe have to slightly bend a rod or two, yet maybe not even that.

Your biggest problem would be in finding one; and I'd suggest you find a complete unit/system, as parts are difficult to find. Should you be fortunate enough to locate one, installed correctly it would make for a sweet-operating vehicle.

It has a 70% gear reduction, meaning it would alter final drive of a 4.11 to a 2.88 (The math: 4.11 X.70 = 2.877). Gives best of both worlds, giving 4.11 to get going and 2.88 for cruising above 30 mph--that's approx. where the centrifugally-actuated governor allows driver to engage the od. [You could engage it in any gear so long as the engine would sustain such rpm's to go that speed!] Vehicles with that tranny generally came with a 4.11; altho' it would prolly work fine w/a 3.73--but anything numerically lower would likely lug your engine.

Hope this gives you a little insight into the GM 3-speed overdrives. They look just like the one that slorio led you to.
sam

[frankslagoon]

Originally Posted by luvbowties

Lee, GM's overdrives are complete transmissions not add-on-to-the-end units. Any overdrive from 1955 thru approx. 1969 should be roughly a bolt-in for your truck. (Among these, the earlier were non-synchronized in 1st gear, just like your orig. trans. The latter-year ones were fully-synch'd.)

I've used std. 3-speed floor-shifters and they fit the o/d trannies just like the non-overdrives. I feel sure one would conform to your stock, on the column shifter--maybe have to slightly bend a rod or two, yet maybe not even that.

Your biggest problem would be in finding one; and I'd suggest you find a complete unit/system, as parts are difficult to find. Should you be fortunate enough to locate one, installed correctly it would make for a sweet-operating vehicle.

It has a 70% gear reduction, meaning it would alter final drive of a 4.11 to a 2.88 (The math: 4.11 X.70 = 2.877). Gives best of both worlds, giving 4.11 to get going and 2.88 for cruising above 30 mph--that's approx. where the centrifugally-actuated governor allows driver to engage the od. [You could engage it in any gear so long as the engine would sustain such rpm's to go that speed!] Vehicles with that tranny generally came with a 4.11; altho' it would prolly work fine w/a 3.73--but anything numerically lower would likely lug your engine.

Hope this gives you a little insight into the GM 3-speed overdrives. They look just like the one that slorio led you to.
sam

Bowtie. are you running power thru the gov. and then over to the sol. I thought the gov. grounded the relay and then the power came thru the relay to the sol.

[joedoh]

change your rear gear ratio which is probably around 3:73 or 4:10 to something like a 2.93. it will make 1st gear useable instead of just a splitsecond "get started" gear and will give you some good freeway speeds in 3rd.

these trucks were workhorses, not commuters, so the short gears made for torque multiplication. ever wonder how anyone got any work done on a farm in the 60s without a durmax/allison with 80 gazillion lb ft? wonder how the ~350lb ft was enough for the c50-60s? torque multiplication by gear ratio reduction (two speed rear ends)

so the drawback to a rear gear ratio change will be you wont be able to haul 50 bales of hay anymore or yank stumps out of the ground in 1st gear. you could spend a lot more on a transmission change, or try to find an electric overdrive 3 spd.

[j_lee223]

Originally Posted by joedoh

change your rear gear ratio which is probably around 3:73 or 4:10 to something like a 2.93. it will make 1st gear useable instead of just a splitsecond "get started" gear and will give you some good freeway speeds in 3rd.

these trucks were workhorses, not commuters, so the short gears made for torque multiplication. ever wonder how anyone got any work done on a farm in the 60s without a durmax/allison with 80 gazillion lb ft? wonder how the ~350lb ft was enough for the c50-60s? torque multiplication by gear ratio reduction (two speed rear ends)

so the drawback to a rear gear ratio change will be you wont be able to haul 50 bales of hay anymore or yank stumps out of the ground in 1st gear. you could spend a lot more on a transmission change, or try to find an electric overdrive 3 spd.

I have considered changing my gears and right now being in Cali that would be perfect but once I finish my time here I will be going back to TX. and I would want to keep my 292 pwr for those stumps or that hay. My plan is to build a new work truck with things that where available in the 60s.
Thanks

[j_lee223]

Thanks Sam yes it helped a bunch. I’m going to be on the lookout for that trany. Anyone know what’s the big thing I have to look out for in finding that 3spd OD I have never seen one and which is the best anyone know? I have heard that the 7 bolt is the one to go with but I have no idea.

[luvbowties]

Originally Posted by j_lee223

Thanks Sam yes it helped a bunch. I’m going to be on the lookout for that trany. Anyone know what’s the big thing I have to look out for in finding that 3spd OD I have never seen one and which is the best anyone know? I have heard that the 7 bolt is the one to go with but I have no idea.

Here's a good read on this topic. Enjoy!
>> http://www.speedprint.com/deves50/overdriveindex.php <<

[j_lee223]

Thanks for the help guys

[slorio]

J LEE:
You need one like this

http://www.ebay.com/itm/Chevy-3-Spee...853182&vxp=mtr

Regards,
Steve
New Orleans

[aerotruk63]

We discussed this subject awhile ago. I tried to SEARCH for the previous thread but wasn't successful. As I understand it there's a switch that mounts to the dash that activates a solenoid mounted to the addition to the transmission. Found a bunch on craigslist.org for a guy who was looking for one. I have no literature on this.

[j_lee223]

Originally Posted by aerotruk63

We discussed this subject awhile ago. I tried to SEARCH for the previous thread but wasn't successful. As I understand it there's a switch that mounts to the dash that activates a solenoid mounted to the addition to the transmission. Found a bunch on craigslist.org for a guy who was looking for one. I have no literature on this.

I just have to keep my eyes open for that solenoid.

Anyone have any pics

[ljackson]

In the for 60-66 for sale forum. "Saginaw 3 speed with the Borg Warner overdrive. Unit has been completely rebuilt ready to install. Price $450.00. Kevin 336-420-7638". This may be what you are looking for. I do not know if it has sold or not.

http://67-72chevytrucks.com/vboard/s...ight=overdrive

[faribran]

I have a 1967 model fully syn 3 speed overdrive in my 67 . I am consideing pulling the small block and tranny and doing the ls with 4l60 e..

[SOUTHERN917]

I've ran 3sp. Muncie with the Borg OD for over a year now, and I love it. Not going to break any speed records, but it gets better gas mileage and cuts my RPM's at highway speeds.

[j_lee223]

Thanks a lot guys. There is a lot of great info here. I am now on the hunt for an OD unit and a Muncie 3spd or a sag 4. I will most likely save my m21 for a later project. Are all OD created equal or do I need a specific year that is stronger, better? Defiantly a brog OD correct?

[frankslagoon]

I didn't know they made a Muncie o/d is that the older short 3 sp.? I am pretty sure you can only do the 4 sp. swap with the Saginaw trannys I should in the pics. have ya got a pic of the Muncie 3 sp. o/d?

[j_lee223]

I was under the same impression. I have herd of a Muncie with an OD, don't know if it was a 3 or 4 spd. I read that it needed some work to mate them together. I have never seen any pics there like unicorns. Lol it would be awesome. The only OD I know of for sure for a Muncie is a gear vendor GV but that's more expensive than my trany itself

[SOUTHERN917]

Well I do have the Unicorn hidden under my truck!!! It is a 319 Muncie out of a mid 50's Studebaker or Biscayne. This is the shop manual I used, and I'll try to post pics ASAP!!

http://chevy.oldcarmanualproject.com...55csm0715.html

This is also a place to get solenoid, etc. and he's a really knowledgable guy
http://www.fifthaveinternetgarage.com/parts.php

[frankslagoon]

Originally Posted by SOUTHERN917

Well I do have the Unicorn hidden under my truck!!! It is a 319 Muncie out of a mid 50's Studebaker or Biscayne. This is the shop manual I used, and I'll try to post pics ASAP!!

http://chevy.oldcarmanualproject.com...55csm0715.html

yep that's a Muncie. )/D early gms from 1940 to 1963 I think. Then they changed to the Saginaw 3 speed with the O/D The old ones won't work for the 4 speed conversion and are non- syncro 1st. Heres a pic of some I have in the shed. early Muncie 3 spd. and a early O/d Muncie 3 sp. the main cases are shorter than the sag.

[frankslagoon]

Originally Posted by SOUTHERN917

Well I do have the Unicorn hidden under my truck!!! It is a 319 Muncie out of a mid 50's Studebaker or Biscayne. This is the shop manual I used, and I'll try to post pics ASAP!!

http://chevy.oldcarmanualproject.com...55csm0715.html

This is also a place to get solenoid, etc. and he's a really knowledgable guy
http://www.fifthaveinternetgarage.com/parts.php

thanks for setten me straight on the Muncie , sag o/d deal I just been callen em early and late GM for years. Duh.

[j_lee223]

Nice, pics would be great. It is non synchro right. Can u foat 2nd to 3rd or go from 2nd to 2nd OD? Can u go from 1 to 1 OD to remove clutch time? How do u shift it? The shifter is the unicorns horn I get it.

[SOUTHERN917]

jlee223 it is non-syncro. 1st is too low to reach the 25-30mph required to shift into OD. The governor (25-30mph) regulates the solenoid which allows OD to engage when you momentarily let off the gas. You shift to 2nd, get upto 30mph, let off gas for 1/2 a second and it shifts "automatically" into 2 1/2. If you shift to 3rd from 2 1/2 it will be in OD or 3 1/2. I mounted my kickdown (down shift out of OD) toggle on the dash.

[frankslagoon]

Southern, you can still shift without the clutch into first if the overdrive cable is in. is that correct?