View Full Version : Transmission: Overdrive engagement

09-05-2017, 10:15 PM

Recently acquired a 54 Commander here. The previous owner was selling the car after his dad passed away, and didn't know much about it. He thought he recalled the overdrive working but didn't know how to engage it. With the lever in, it freewheels as it should, and with the lever out, the engine slows on compression. However, the overdrive gear itself never kicks in - to my knowledge, it's just a matter of letting off the throttle at speed, but the guy selling it to me thought it had something to do with the button on the floor next to the brights, near the clutch. Am I missing something here, or is it an issue with the solenoid?

Also, what does that button next to the brights do?

Thanks in advance!


09-05-2017, 11:23 PM
/Cut/and with the lever out, the engine slows on compression./Cut/Paul

When the Handle is OUT it is in conventional Dive with compression, it will not shift to O.D.

Nothing important, it JUST Starts the Engine! Or at least it "DID". :ohmy:

Not knowing that, tells me he probably would not know how to make it shift to Overdrive. (Handle IN, 32 MPH and release the Gas Pedal in 2nd. or High.)
But no worries, if it does not you'll get 6 people here telling you how to fix it! :D NO big Deal.

NOTE: ALWAYS REMEMBER TO PARK THE CAR IN REVERSE, that way, it will not matter if you left the O.D. in or out, forgetting that MAY have it rolling away!

09-06-2017, 10:01 AM
The button on the floor should be the starter button that is engaged when the clutch pedal is fully depressed. How is the car started now?
Like Rich said, you need to be going around 30 MPH for the overdrive to drop in. Accelerate through the gears with the handle in and then lift your foot for a moment and the overdrive will engage. In my old car the overdrive would sometimes stick and take more than one try right out of the garage. If it still refuses to work, then it's diagnosis time. I recently repaired the overdrive in my 52 Commander and I am loving it on the highway.

09-06-2017, 04:09 PM
The shop manual gives a step by step troubleshooting guide for the overdrive, but it only applies if the system is still original and correctly wired. If the car has been converted to 12 volts the electrical wiring will be different than the original 6 volt system. I would suggest first examining the system and verifying what you have as well as inspecting all electrical connections and wire condition.

09-07-2017, 11:19 AM
Thank you for the info everyone! The system is the original 6 volt, all original components. The overdrive won't engage at speed at all, so I feel like a service manual would be my best bet. Where can I find one?

09-07-2017, 01:46 PM
Studebakervendors.com have all the manuals. Buy all three as there is much information contained that will answer many future questions.

Did you check the fuse on the overdrive relay? It's on the firewall.

One of the biggest contributors to overdrive NOT engaging is the governor, on the rear of the transmission. The seal leaks, the governor gets filled with oil and cruds up the points. You can put a temporary jumper wire on it and bring that jumper into the passenger compartment. When driving, connect that jumper to ground and see if the overdrive engages.