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Ok, this may seem like an odd question but I'm still learning my car a bit (only had it a few months now). I am not sure if I am my overdrive kickdown is not engaging or I'm just living with a poor memory.

When I am driving, I seem to recall hearing/feeling the kickdown a bit more pronounced around 30 mph when I engaged it after easing off the gas. I ended up not being able to drive for a month (various reasons) and now I am not sure if I imagined the way the kickdown was running before or if it isn't working/engaging.

Question 1: Is the change as obvious as I remembered? The car still goes say 45 mph and while it sounds like it's running a little high, it's quiet enough I can't sense it's running super hard (cf. like running in 2nd above 20 mph).

Question 2: If my memory is right, tips for checking, unsticking, etc.? I'm also a mechanical novice so being super descriptive and talking a bit "down to me" is appreciated.

You should hear a noticeable difference in engine speed. Just like changing gears from third to fourth.

Question #2 I leave to people like Pat Mescher.

West is correct; think of the transition into OD as another gear.

As with any manual gear shift, a shift from one gear to another is smoothest when the driver has perfectly matched the engine output speed with the transmission input corresponding to the vehicle speed. When done perfectly, there is no speed and very little torque difference between the engine output and transmission input. To make it a little more challenging (or fun if you are like me and love to drive manual transmission cars) is that the engine speed isn't constant. It will be slowing from whatever speed it was at before you changed gears; therefore, the challenge is multifaceted. Wonderful things like clutches and synchronizers make this much nicer in a manual transmission.

So, for an overdrive, there is also such a sweet spot, or range. Unlike a transmission, there are no syncros damping the transition. Nor is there a clutch, however, at the moment before OD engagement, the transmission is free wheeling and allows for zero torque in order to complete the OD engagement. The clunk you may hear or actually feel is the sudden coupling of wheels to engine, in which now instead of free wheeling, the engine is slowing the car. You feel the change from just coasting to engine decel.

So, with all that, I have found that cars with different engines, rear end ratios have diffrerent sweet spots. The suggestions I have for you, below can both be summed up as "Get Out and Play!"

•Play with different speeds at which you allow engagement. I expect you find a speed that is almost silent as well as nearly unnoticeable.My experience is that if you wind up the engine and delay allowing it to shift into OD, the degree of sound and rate of decel change is much more.

•Play with letting off the gas pedal gently, Do it across several speeds to get a feel for it. At higher speeds, this will lessen the sound as well as the abrupt change in decel since slowly backing off will allow for OD transition while the engine speed is still higher.
All of the Borg Warner ODs Packard used, the R6, R9 and R11 exhibit this, but are very robust.

Get out and play.

I guess that is where I am thinking it isn't working anymore. The let's say 10-15 times driving after I first got it I felt like the overdrive was more pronounced and aligned with that roughly 28-30 mph kickdown and seemed noticeably quieter and if I was guessing like your car going from 3000-3500 rpm to 2500 rpm (seeming like shifting up a gear).

I'll keep driving and experimenting to confirm my suspicions and may setup a camera/mic to verify what I think I am hearing/feeling. I guess it's not legal for one of my kids to ride the fender and running board anymore and report back.

Short of replacing OD, are there any tricks to troubleshooting the OD or is it a replace scenario?

Thanks.

Well, again citing West, you should be able to tell by engine noise, along with the change of engine braking when in OD vs free wheeling before you get into OD. Perhaps find a hill that allows you to reach engagement speeds and disengagement speeds safely, drive up and down to observe the transitions. This can help to amplify the effect.

Regarding means to repair or correct, you'll need to have much more data before concluding you need a replacement system. Your car should have an [edit R9 R6], which has an internal governor, not an external with electrical circuitry to engage the OD (Regarding disengagement, there are two means to get out of OD: either getting to such a low speed the centrifugal governor disables, or, the electrical kickdown in which if you press hard on the gas pedal, a switch drives a solenoid to disable OD). So, for engagement, there isn't much to diagnose except possibly a solenoid that is, for some reason, always energized, preventing OD.

Other than that, if you haven't changed transmission oil or know when it was last done in case the car sat for a long time, that may ultimately be something to try. I have successfully 'woken up' several units whose engagement parts were stuck in old jurassic oil by flushing out the old oil with kerosene and refilling (DO NOT drive with kerosene, however). If you are energetic, there is an access hole in the floor that allows access to a top plug in the OD casting that can be used for flushing (pretty sure this is the same plug that allows access to adjustment of two governor preload springs that control engagement speed).

I realize you believe you are not mechanically savvy, but I still urge you to try to review the service and parts literature. In the meantime, it seems, back to West's point and mine, you can gather more data by making sure you can detect whether the car is still freewheeling or in OD. Get out and play.

One minor clarification to what is probably a typo in 39SixSedanMan's comments but if the car is stock a 39 would have the one year only use by Packard of the R6 semi electric overdrive. The R9 full electric model was used from 40 to mid 48 and then that overdrive was discontinued and the R11 model was used until the end.

Packard did provide some basic information on the R6 unit but since it was one year only there is not nearly as much service info as is available for the other units. There are a few service letter articles, one in particular on making sure the lockout cable is adjusted properly to prevent the unit from being in a freewheeling condition.

As an aside, note the addition of a reverse switch and different relay on later production. With that change I suspect they found the R6 may have had an issue of locking up if reverse was desired and for some reason it had not dropped out of overdrive when stopped. Adding a switch to forcibly energize the solenoid in an R6 would ensure overdrive was inactive in reverse. R9s were also found to have the same issue and those too had a switch added which was activated in reverse. In the R9 application the switch cut power to completely disable the OD electrically to ensure it could not stay engaged. The R11 was a thorough mechanical redesign and was no longer affected by the issue.

Here is a bit on troubleshooting the R6 that was published in a Motors Manual of the period. It may not be of much use to you if you are not a mechanical type but perhaps a friend or local mechanic might find it useful and could help in seeing if at least the electrical items function as described.

Attach file:

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  R6 OD.jpeg (305.46 KB)

Yep...meant R6. Edit to post made. Thx Howard
Pat

Like many things I know enough to be dangerous. Leaning on the experience and advice of others is appreciated. It's a balance of learning from others and learning from mistakes with the former usually being cheaper.

Thanks to all. This definitely gives me some good direction and I hope to be able get to this next week and sort it all out and report back.