Packard Forum Index » Post-War (1946-54)

I bought a 1947 Custom Super Clipper late last year and only managed a few short low speed trips before the winter storage season. Overdrive was disengaged for all of them and has been since I bought it and I'd now like to do some highway driving and exercise the overdrive unit. The instructions for use from the previous owner were confusing and unclear so I am hesitant to just do a trial an error run to figure out how to properly engage, use and disengage overdrive.

I've looked through much of the literature in the archives here but didn't come across any driver/user instructions - mostly service information. Can anyone help with some clear how to's, do's & dont's etc? I recall warnings about engaging or disengaging while in motion and cautions about only using it above a certain speed but I'm not clear about the real rules governing use. Thanks in advance for any insights and assistance.

If you car is stock, it will have the R9 overdrive and here are instructions for the operation as taken from the 47 owners manual.




If your car is one which an owner might have paid to have the OD changed to the newer R11 overdrive because of the Reverse gear lockup issue detailed in Service Counselor Vol 21 #15, the operation is almost the same but on the R11 the indicator light mentioned in the R9 instructions is no longer functional. On that OD you need to depend on your senses to estimate the speed and time when OD will become available. Here are the instructions for the R11.




If you are unsure which OD you have, look for the OD relay on the firewall area in front of the driver. The R9 will have a large squarish black box with 6 terminals. It is about the size of a voltage regulator and located roughly below the coil and slightly below and more toward the engine than the voltage regulator. The R11 will have a smaller rectangular shape relay most often in a natural zinc color but some have been seen painted. That relay has 4 terminals, two on each end with a fuse mounted on the forward facing long side.

Thank you Howard - much appreciated. I have the stock R9 unit. The instructions about controlling the on and off state of overdrive while driving is clear. However, just so I am clear about moving the lockout knob in or out, it looks like any movement of that knob should only be done while the car is in motion and above the noted engagement speed of overdrive. Is that correct?