3 speed with overdrive info please!

[Hawks]

When i bought my 60 c20 it has an 3 speed with overdrive. I have never really seen 3 speeds with overdrive much. I have got it on the road a few months ago and have been driving it every day. I dont use the overdrive much. Im not exactly shure how it works. I have done a little research on it. i know it has the four bolt side cover so it should be pre 1966 right? With the non synchronized first. And im not shure what the box with the fuze is on the firewall or the button on the floor. i was thinking about just putting in a four speed. and was just wondering what this set up is worth also? Thanks for any help

[k1rodeoboater]

Does it work? If so I'd be interested if you decide to part with it.
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[Gianyveedub]

What you have there my friend is a gift. Those have a overdrive ratio of .70:1. That overdrive is better than most T-5's that many members here put in. The box on the firewall is the relay needed to run the system. The button on the floor by the gas pedal is for when you floor it, it will cut the Overdrive out and run 1:1 to help you pass on the freeway and re-engage the Overdrive when you let off the floor. The Overdrive cable is to lockout and engage the planetary gears of the Overdrive (when going up hill or around town). If you need more info PM me and I'll give you the long run down..

[slorio]

Agree with Gianyveedub, it is truly a gift. Don't part with it. You might want to clean its "patina" up a bit. Here's the literature on these trannies. Read all about it!

http://speedprint.com/deves50/overdriveindex.php

http://www.classictruckshop.com/club...5n/rebuild.htm

http://www.classictruckshop.com/club...cts/how_to.htm

Regards,
Steve
New Orleans

[Hawks]

Originally Posted by Gianyveedub

What you have there my friend is a gift. Those have a overdrive ratio of .70:1. That overdrive is better than most T-5's that many members here put in. The box on the firewall is the relay needed to run the system. The button on the floor by the gas pedal is for when you floor it, it will cut the Overdrive out and run 1:1 to help you pass on the freeway and re-engage the Overdrive when you let off the floor. The Overdrive cable is to lockout and engage the planetary gears of the Overdrive (when going up hill or around town). If you need more info PM me and I'll give you the long run down..

The button is by the headlight dimmer switch. i dont see anything around the gas pedal. Also would this system throw off a tach i cant seem to get mine set right. think for all the help. i drove home with it engaged today and i think it is working well.

[gor in san diego]

Originally Posted by Gianyveedub

What you have there my friend is a gift. Those have a overdrive ratio of .70:1. That overdrive is better than most T-5's that many members here put in. The box on the firewall is the relay needed to run the system. The button on the floor by the gas pedal is for when you floor it, it will cut the Overdrive out and run 1:1 to help you pass on the freeway and re-engage the Overdrive when you let off the floor. The Overdrive cable is to lockout and engage the planetary gears of the Overdrive (when going up hill or around town). If you need more info PM me and I'll give you the long run down..

Hey let me get in my two bits....An overdrive three speed in a C-20 sounds a litle weak... but never mind. I had a 57 Chevy two door wagon, 283 with the OD tranny and a 4:11 rear end, stock. I put in an 098 Duntov cam and a Carter four barrel carb. The original downshifter was on the carb linkage which activated the electric solenoid down shifter on the tranny. (later it was on the floor?) I mounted my downshifter with a button on the dash. If you knew how to run it, it would go...You really had a 5 speed. I know this is a truck forum but I couldn't help myself.

[Hawks]

I was thinking it may be a little weak to. but im not shure. i do a lot of hauling with my truck. i would hate it if i messed it up. It shifts great now and i keep fluid in it so i hope it will be ok.

[gor in san diego]

Originally Posted by Hawks

I was thinking it may be a little weak to. but im not shure. i do a lot of hauling with my truck. i would hate it if i messed it up. It shifts great now and i keep fluid in it so i hope it will be ok.

If you want a working C-20, find a 4 speed granny tranny....indesructible, will require some drive train work. The three speed OD may be worth some bucks in the retro Chevy car field.

[Gianyveedub]

The O/D can mess with your tach....what I mean is that when you hit the switch(in your case) or floor it, the O/D cuts the engine power for a split second to ease off tension from the tranny to shift into 1:1 ratio for passing. This in turn will cause the tach to act funny at times, but under normal driving it should not cause any problems. Hope this helps

[qksilver]

I have all the parts you would need to convert to a 4 speed with granny gear and sure would love to have that overdrive set up for my 66 1/2...............pm me if interested, I am not that far from you, I am by Fayetteville NC.

Thanks,
Steve