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

The R-9 or R-11 overdrive. Did any other car makes use these overdrives and would they fit a Packard 3 speed? I assume the output shaft of the transmission is different between a Packard three speed with overdrive and one without?

Thanks John

Other cars did use a version of both ODs with the same internal mechanicals. Prior to 55 Packard built their own transmissions so the adapter plate which bolts between the trans and OD and all those parts involved in mounting the OD including possibly the OD outer casting holding the OD mechanical parts is Packard specific.

The front U joint varied by model and year between units made by Spicer or Mechanics so the OD output flange would be dependent on which U joint was used.

There are plenty of Packard Overdrive transmissions out there to be had, depending on what year car you are working on, or if earlier car, it is possible to adapt a topshift cover to a later/pverdrive transmission.
see:packardinfo.com/xoops/html/modules/newbb ... m=12&post_id=125194#forumpost125194

PTV,
Indeed, many other manufacturers used various versions of the Borg Warner OD from the R6-R11. I believe it is Ford that actually used a version until 1972 or 73.

Although some of the internal components were common across the R versions and across different car manufacturers, the Packard OD outer case and adapter plate are unique to Packard.

I have an old Hollander or other parts interchange that includes all the BW interal part numbers and I've wanted to both digitize it and build the cross references specific to Packard such that any of us could know which internal part would cross from an R-11, R6 to an R-9, or from a non Packard version to a Packard version. Just haven't got to it.

However, if you find yourself needing a translation, I'll be happy to look up things and post.
Pat

Thanks everybody. I may have other questions about this down the line. Flack that is a good article on modifying to a top loader on a newer box.
John

Never having drove a car with overdrive. Can one downshift with the car in overdrive, say from 3rd to 2nd or vice-versa? Or does the overdrive need to be disengaged first? I know there is a lockout for reverse and low would not be fast enough for overdrive to engage.
John

Yes you can down shift, however most if not all overdrives have a sprague (sp) clutch which disengages on deceleration. You are then freewheeling and have no or very little engine braking. Therefor it is recommend that you disengage the overdrive in steep mountains. Overdrive are great as you can stay with the traffic, even better if you can find a none overdrive third member with a lower ratio.

Yes, you can upshift and downshift while in overdrive. If above the engagement speed, a downshift from 3rd overdrive to 2nd will result in being in 2nd overdrive. Of course don't expect any engine compression braking in any overdrive gear due to "free wheeling"; when approaching long and steep downgrades it's often advisable to disengage the overdrive.

Whoa, that is not quite correct. Once the car is above engagement speed and the overdrive is operating (knob pushed in) you will have engine braking in 3d over and in 2nd over. Below engagement speed the car will freewheel.

Still, in mountainous driving it is good to lock out the overdrive not only to prevent frequent need to kick down while climbing, but also to have engine braking at every speed.

Brain malfunction, I stand corrected, thanks Ross.