Adding Overdrive

597LSCJ
Last seen
Joined
Jul 23, 2018
Thunderbird Year
1959
I am adding an overdrive transmission to my 59 convertible with the factory 3 speed, does anyone have a photo of where the factory installed the overdrive relay? How about the factory location of the overdrive kick-down switch? Any help is greatly appreciated.
 
I am adding an overdrive transmission to my 59 convertible with the factory 3 speed, does anyone have a photo of where the factory installed the overdrive relay? How about the factory location of the overdrive kick-down switch? Any help is greatly appreciated.
On my 57 T-bird the relay is on the firewall kind of in the middle on the lower half and the kickdown switch is under the gas pedal. Just a reminder if you put in that overdrive transmission you really should have the overdrive rear end that goes with it. Which would be something in the neighborhood of 3.7 rear end ratio. I found any higher ratio than that next to car not drive well at low speeds.
 
I am adding an overdrive transmission to my 59 convertible with the factory 3 speed, does anyone have a photo of where the factory installed the overdrive relay? How about the factory location of the overdrive kick-down switch? Any help is greatly appreciated.
I suggest you look in your shop manual for these locations.
 
On my 57 T-bird the relay is on the firewall kind of in the middle on the lower half and the kickdown switch is under the gas pedal. Just a reminder if you put in that overdrive transmission you really should have the overdrive rear end that goes with it. Which would be something in the neighborhood of 3.7 rear end ratio. I found any higher ratio than that next to car not drive well at low speeds.
Thanks for the reply, I bought a used OD transmission and it had an odd looking kickdown switch on it. Doing some research I found out that it actually mounts on the firewall and when the throttle is depressed the linkage comes back towards the firewall and depresses the switch, which is nothing like the factory 59 T-Bird switch that is under the throttle pedal. My first car was a 57 Fairlane with a 3 speed OD, I'm looking forward to getting the OD up and running on my 59. I have found some photos of the location of the relay on the 55-57's but nothing on the later years yet.
 
Thanks for the reply, I bought a used OD transmission and it had an odd looking kickdown switch on it. Doing some research I found out that it actually mounts on the firewall and when the throttle is depressed the linkage comes back towards the firewall and depresses the switch, which is nothing like the factory 59 T-Bird switch that is under the throttle pedal. My first car was a 57 Fairlane with a 3 speed OD, I'm looking forward to getting the OD up and running on my 59. I have found some photos of the location of the relay on the 55-57's but nothing on the later years yet.
I have a 57 Tbird. it came with a 3-spd non-OD transmission. I bought a parts car for another project (57 Ranch Wagon). the parts car had an overdrive transmission. The OD in the parts car was not original as far as I could tell. The input was a fine spline rather than the coarse 10 spline. The OD on the back of the T85 was also different than I would have expected, ie. shorter and stockier. I got the relay and the engagement cable from the donor parts car. The kick-down switch was toast. When I wired up the solenoid and governor to the relay I left the kick down switch off. I just dead ended the wiring for the switch. This wiring is shown in the Borg Warner T-85 overdrive manual. If you search around on the internet you can find this manual at no cost. You may likely need a new driveshaft or have yours modified, all of the ODs are not the same length.
The Y-block is not a high rpm engine but it does have plenty of low end torque. I think the fact that the Fordomatic transmission unless specifically put into low gear , starts in second gear. I have not felt the need for the kick-down. What the kick-down switch does is supply a momentary ground to allow the transmission to disengage overdrive. Usually this for passing. The kick-down switch is traditionally under the gas pedal on the kick-up of the floorboard actuated when full throttle is applied for passing or accelerating in high gear. I assume you probably know this as you said you previously had an OD car.
When I was young, a friend's parents had a '59 Thunderbird with 3 speed w/ overdrive. Occasionally I see an OD bird for sale. If I was in the market for a square bird I would want a '59 with overdrive. I don't remember where the relay was located. I would presume it would be in a similar location to the '57 fords. You may find a picture of a '59 fullsize or less likely a 'Bird. I would try E-bay for cars for sale. I would also search '59 Ford images and '59 T-Bird images. If there is any luck You will find the location. By the way do you have the 352 or the 430? Either one probably will not demand the use of a kick-down switch. Also do you have AC. I would think that the location for the relay would be placed so as not to interfere with the AC suitcase that is factory mounted behind the engine on a sort of shelf directly in front of the center of the firewall. Good luck and happy motoring.
 
Thanks for all the info. my engine is a 428 SCJ block with mid 60's 390 heads and an intake off of a 63 427 low riser as in a Galaxie. I downloaded the repair manual this morning and there was no location given as to the whereabouts of the relay. I will find it, I did Google 59 Thunderbird and looked at the images but all there was were images of the 55-57's. The manual did contain some good troubleshooting and images of the parts but no real locations. No AC wish it did! I was lucky in that I was able to locate a T89 w/R11 overdrive so it is the heavy duty model used behind the FE's in the 60's. This past weekend I purchased another T89 but this one is a truck version with the shorter tail shaft and the yoke bolted to the output shaft. All is good, I've got a number of spare parts now so I hope to get everything bolted up by the first of the year. My car is an original 3 speed manual car that has been converted to a 5 speed T5 with a G-Force heavy duty upgrade. Everyone thinks I'm nuts for wanting to take the 5 speed out but 3 on the tree with OD will be different.
 
Thanks for all the info. my engine is a 428 SCJ block with mid 60's 390 heads and an intake off of a 63 427 low riser as in a Galaxie. I downloaded the repair manual this morning and there was no location given as to the whereabouts of the relay. I will find it, I did Google 59 Thunderbird and looked at the images but all there was were images of the 55-57's. The manual did contain some good troubleshooting and images of the parts but no real locations. No AC wish it did! I was lucky in that I was able to locate a T89 w/R11 overdrive so it is the heavy duty model used behind the FE's in the 60's. This past weekend I purchased another T89 but this one is a truck version with the shorter tail shaft and the yoke bolted to the output shaft. All is good, I've got a number of spare parts now so I hope to get everything bolted up by the first of the year. My car is an original 3 speed manual car that has been converted to a 5 speed T5 with a G-Force heavy duty upgrade. Everyone thinks I'm nuts for wanting to take the 5 speed out but 3 on the tree with OD will be different.
Unless they are paying your salary the other people get no say in what you do. The transmissions you picked up should be essentially the same as far as the internals. I like the sound of your car. There are some other sites about fords that should be useful. Just keep putting in different variations of the search criteria. There must be a Ford internet group out htere somewhere. In Northern California there is the ************************ for 1958 - 1966 birds. There has got to be something helpful. Good luck, john
 
Back
Top