3 speed overdrive
 

Found a 3 speed manual overdrive to replace my four speed in 65 c10. Need to know if anyone has a picture of where the overdrive cable is supposed to be mounted under the dash, and more importantly to me is where the cable would have originally gone thru the firewall at.

Re: 3 speed overdrive
 

I had a new '64 that I ordered with overdrive and the handle was mounted on the underside of the dash below the heater controls, if I remember correctly. Can't help with the route thru the firewall as I never looked.

Re: 3 speed overdrive
 

Here’s where I put mine, just make sure where you route it so that it doesn’t make any sharp angles or kinks.

Re: 3 speed overdrive
 

I thought the overdrives were electric, but what you have appears to be some kind of cable??

Re: 3 speed overdrive
 

Thanks CRUZN66 that's where I was kinda thinking to put it. Do you happen to have a picture or the engine side?

Re: 3 speed overdrive
 

On a stock firewall this pic by racecougar is the info I know of (that doesnt mean much). :)http://i6.photobucket.com/albums/y20...alldiagram.jpg

Re: 3 speed overdrive
 

I know mine is a 63, but I believe mine was either factory installed or dealership installed. My overdrive handle is the knob in the dash closest to the left side of the steering wheel. If you look right above the firewall plug for the headlights and turn signals, that is where the OD cable runs out of. It is a straight shot from the dash to that hole in the firewall

Re: 3 speed overdrive
 

When the cable is pulled out it locks out the overdrive so the transmission isn’t free wheeling any longer.

Re: 3 speed overdrive
 

It’s hard to see from the engine compartment, because it’s behind the left head. I’ll see if I can get a picture tomorrow, however here’s another picture of the interior and if you zoom in you can see it where it goes past the back of the gauges and through the firewall just above the gas pedal and carpet towards the hump.

Re: 3 speed overdrive
 

Here’s a better picture of the inside of the cable and a picture of the cable from the engine compartment however you can barely see the cable about in the center go down by the oil filter under the corner of the engine & bell housing.

Re: 3 speed overdrive
 

When I installed the O/D in my 63 I put the cable mount below dash just right of steering column. However, I have NEVER used it. If I was doing it again, I wouldn't put it in.

Re: 3 speed overdrive
 

Tuesday evening I went to a cruise in, and about 2 miles from my destination, something went wrong with the electrical system I think (have not had a chance to look at it). I lost overdrive but the trans would freewheel above the cut in speed. To get home, I pulled the lockout cable and drove as if I had a standard 3 speed. I like to have engine braking especially at highway speeds.
If you were to ever need to push start to get home, locking out the trans is necessary. Yes, that's a rare occasion, but still could happen.
Also, you can use lockout while rolling in traffic that makes you go in and out of overdrive every hundred feet or so. Makes it less annoying to me by just staying in 2nd gear.
Just my 2 cents. I love my overdrive, but I sure hope that my solenoid didn't crap out on me

Re: 3 speed overdrive
 

Tanks for the replies guys! It will be a month or so, but trying to get a plan together.

Re: 3 speed overdrive
 

Happy to help!

One more suggestion is to test the relay, solenoid, governor, and kickdown switch before you put the trans in the truck. I didn't do that to mine and ran into a bad relay and had to pull the solenoid to adjust the contact points inside it after I had put the trans in the truck and filled it with gear oil. A full trans will pour out the overdrive solenoid shaft hole if you have to pull the solenoid

Re: 3 speed overdrive
 

will do!

Re: 3 speed overdrive
 

I just had mine stop going into overdrive. It all started with my alternator going out.

Ya see.....I ran the power for my relay from the headlight. Two reasons. It was close to where I mounted my OD Relay and I had already installed a kit to run the headlights all the time (daytime running lights). Ok 3 reasons. #3 I'm lazy.

Apparently what happened was the bad alternator caused the fuse to blow on the daytime running lights and cut power to both the lights and overdrive relay. Turns out all I need to do was turn on the headlights and it would have got me home with overdrive.

Check for power at the fuse on the relay. If no power, start there.
You can also jump power to the solenoid there at the relay. A heavy click is a good sound.