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That's another thing I noticed. Sitting in the car with the drivers door open and tapping the accelerator pedal...I can look down at the ground and see that the car appears to try to move forward in PARK or NEUTRAL when the engine RPM's increase so I'm suspecting that it's sending pressure somewhere that it's not supposed to...or at least I don't think it's supposed to.

It may be that gear selector adjustment and tv linkage adjustment might do wonders for your tranny, if they're both off.

Yes, check all adjustments FIRST; else, your pressure test results may be in error.

In addition to the shop manual, you should review SC Vol. 27, No. 2 (starting pg. 7), which covers the latest updates relative to linkage adjustment for 23rd-26th Series and is nicely illustrated.

This is also covered in SSB No. 340 (starting pg. 5) for 23rd-54th (exc Gear Start), but wth a revised (one-size-fits-all) version of the special adjusting gauge. This document also includes relative dimensions for the checking throttle control rod (see pg. 7).

Last but not least, see this thread for an alternate approach to for the special adjusting gauge - with "a tip o' the hat" to HH56. (Click on his attached JPG image to enlarge.)

I'm thinking that driving an Ultramatic without the lockup is quite different in the V8 cars than the pre-V8 Packards.

One experience was a '55 Clipper that did not shift into lockup and was driven normally for many miles over it's later life, at speeds often exceeding 70 mph.

Perhaps the V8s had a lower (numerically) final drive ratio? Also, there is no change in gear ratio with the lockup--just the elimination of slippage--indicating that the torque converter in the pre-V8 cars might have had more inherent slippage, hence making the "feel" and higher RPM so noticeable when the lockup doesn't engage. The more slippage it eliminates, the more difference would be felt on lockup.

Just some observations on which more knowledgeable people might wish to comment.

P.S. That Clipper Twin Ultra never did fail, except in respect to the lockup feature.

Many thanks to everyone who contributed to my request and to you BH for the links and to HH56 for the gauge dimensions. I didn't realize that there were as many adjustments as there are and the critical parts they play in achieving correct transmission operation. Like I said, I'm in the learning stage of ownership with this car and without having another car to drive and compare it to is like driving in the dark without headlights. I'll move forward with making the adjustments first and see if direct drive can be accomplished. If not then I'll perform the required pressure tests and see what turns up. Hopefully it's nothing too serious...

G'day all, There are very few adjustments to the Ultramatic and Twin -Ultra ( same as the ultra but with an optional shift from Low range band to High range clutch)
The Ultramatic is a very good box but has a few problems when bush and shaft fitments enlarge, particularly in the high range clutch area. Packard used these bushes as seals and it was in my opinion a good move at the time, but prone to abuse if the fluids were not changed very regularly. This wear/pressure problem occurs where the front and rear pump pressures enter the gearbox output shaft to pressurise the High Range Clutch and the Direct Drive Clutch.
Essentially in High Range the initial take off is using the Front pump and converter. The Governer kicks in when it flings around enough to energise the converter valve which awaits a signal that the rear pump pressure has overcome the throttle pressure, at which time the Direct Drive Clutch will engage and the Front pump will go to idle. This smaller rear pump now pressurises the direct Drive Clutch and High range clutch packs, therby allowing the oil to cool
I note that many contributors to this topic have mentioned over-revving in high range and I would suggest that in many cases this is slippage in the Direct Drive or High Range Clutch packs.
I would strongly suggest that if you are at light throttle at 40 MPH, back off and then put a reasonable amount of throttle (say 30%)and try to pick when it starts to slip or the road speed to engine revs increase does not respond like a manual vehicle. then you have a problem which can easily toast your box. Linkage adjustments are confined to throttle pressure and would have no effect after 50 mph anyway. Best regards Peter Toet

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Thanks for that detailed account of how the Ultramatic Direct Drive operates Peter. I am definitely one for seeking to understand how it is supposed to work but even more, I was glad to hear that it's a good transmission which of course has a lot to do with exactly that...understanding how it works. It was bitterly cold here in North Florida yesterday and I didn't get to take the car out for a drive after work as I had planned however I will say this...there were two outstanding charcteristics that I noted during the two times that I drove the car. first and foremost is that there was no slippage whatsoever...with the gear selector in the "HIGH" position, the car started out and responded as if it was in "LOW" range...it was very responsive and did not display the sluggish take-off that others have described as a charcteristic of the ultramatic when starting out from a dead start in "HIGH". The second thing I observed was that there was no defined "locking up" of the converter and therefore no drop in engine RPM's. The car increased speed as did the engine RPM's but there was no slippage.

When I have an opportunity to drive the car again, I will place the selector in "LOW" range and manually shift it to "HIGH" range at around 25 to 30 MPH and see what happens...is there a chance that incorrect throttle valve position is not allowing the high "HIGH" range/direct drive feature of the transmission to operate at all?

The only time the converter doesn't have any slip is when the direct drive clutch is engaged - at "cruising" speeds. If the torque converter wasn't able to slip, not only would you not get the benefit of torque multiplication, but the engine could be prone to stalling at low speeds. Several newsletter articles were devoted to that very problem - when the direct drive clutch failed to disengage. Check out the Ultramatic section of the 1951-54 Service Index.

Prior to the Gear Start edition, there was NO automatic up- or down-shift betwen Low and High range in the Ultramatic. So, the sensation of "LOW" range operation with selector in "HIGH" in your car could be a matter of control linkage adjustment or internal pressure leaks.

Try to think of an automatic transmission as a hydraulic computer. The Ultramatic considers inputs, like:

- selector position (via control/manual valve position)
- throttle position (via throttle valve pressure)
- vehicle speed (via governor pressure

...and then determines outputs, redirecting pump pressure to apply/release:

- reverse band piston
- low range band piston
- high range clutch piston
- direct drive clutch piston (pressure plate)

Now, there are some other control valves and regulators involved in the greater processes, but I'm just pointing out the basics to show why adjustments and pressures are important. Another adjustment to check, WRT to your previous observation of creeping in neutral, would be band adjustment.

If all adjustments are in order and the manual valve is in correct detent, but pressures prove to be out of line, the test results should give you some idea of where to look, next. The path might very well lead you to worn bushings, pumps, etc., but until you've covered the basics, you're just guessing.

BTW, have you drained the trans and converter and refilled with fresh fluid? Tired old fluid can gum things up. Also, inspection of the contents of the pan may be quite telling.

While you're at it, you may want to clean and inspect the governor, as its operation (in addition to the throttle valve) also affects the timing of direct drive clutch engagement. Prior to the Gear Start design of late '54, the governor can be accessed by removing a cover on the right rear of the transmission case.

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Brian,
Yes I did...I drained both the transmission and the converter and cleaned the filter screen. there was no debris in the pan or screen but there was kind of a gray film coating the surface of the internal transmission parts. I checked as much as what I knew how to check while I had the pan off...I replaced the pan gasket and the selector shaft(cross shaft)seal. The old fluid was a dark red but didn't smell burnt. The PO sid he was told to use Dexron however based on the general consensus of the forum, I went with type "F" for the refill. That's it, all of the gears hit their respective detents when and where thsy should and the car moves forward and backward...I described it to HH as feeling like it has two "LOWS" and no "HIGH". The "ever so slight" creep I described occurs in both NEUTRAL and PARK when punching the throttle but it's not bad enough for the car to roll...it's really barely noticeable however HH flipped a switch in my head...is there a possiblity that maybe somone overtightened the LOW band when they misdiagnosed the normal and somewhat sluggish operation of HIGH as being slippage? as it is now, anyone that didn't drive the car over 30 or 35 would say it was fine if they didn't think the RPM's were excessive. If I understood HH correctly, an overtigtened band would cause the tranny to remain in LOW and would prevent normal operation of HIGH and ultimately DD lock-up...did I understand correctly?

If you read the Twin Ultramatic "Trouble Shooting..." section in the 1955/56 shop manual, overly tight adjustment of the low band is the first listed cause for creep. There are several others you might also consider.