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

Quote:

Roland, I haven't gone for a drive yet to do some experimenting, but I think our transmissions are working as this states, but it us that are not accustomed to how they work.

On our modern transmissions, for example 6 speed with overdrive and several inputs controlling them, we don't have to depress the accelerator pedal much and they kick out of overdrive, depress the pedal a little more and they drop down a gear, etc.

But with our Ultramatics there is only one input that disengages the direct drive, pedal ALL the way to the floor. "Beyond full throttle!" I think our throttle linkage adjustments being correct are important for everything to work correctly, for the DD to engage with the correct amount of pedal (relative to speed), and to disengage with the correct amount of pedal (also relative to speed).

I see humanpotatohybrid also commented similar thoughts, hadn't read his post before I wrote mine.

53 Cavalier wrote:

On another note, if the DD clutch is not replaced, and hasn't been replaced previously, then using modern ATF is a no go, correct? That is, the material used to make the clutch are not compatible with modern ATF. Is that correct?

Incorrect, there's no reason you can't use modern ATF with original materials. FYI, this image shows the original cork type lining.

When I get home I can grab a picture of the new linings people use.

Are clutches expensive?

I sell the 9 inch ones for $160 ea + core. And I have good used ones for even cheaper. (Max Merrit is at $195.) But you need to know which one you need.
410835 - 11-3/4" used on the very earliest transmissions
436411 - 11-1/4" used afterward
423415 - 9"
423667 - 9" revised part
450678 - 9" revised again (I don't know what the difference was on these; they are impossible to tell apart from the 423667. I suspect the new chamfering pattern.)

Hence, realistically speaking, there are only 2 types: 436411 and 450678.

Does it not make sense to replace this wear item if you have your torque convertor apart? I would have assumed the answer is yes, but maybe I'm mistaken.............it's happened before!

You can easily do the "fingernail test" to a clutch soaked in fluid as shown in Ross's video. If it passes then you might as well throw it back in unless you really plan to drive 30k+ miles.

I think our throttle linkage adjustments being correct are important for everything to work correctly


Truth be told, even this is an understatement.

It’s a bit difficult to give more detail when I’ve not driven my cars any distance for decades but both of my 1953s (Clipper Deluxe and Patrician) and my 1954 Patrician never got “stuck” in direct drive as I understand the issue here is and would drop out of it at slower speeds. As I recall, that was somewhere around 30mph and I never had to floor any of them for it to do so. While I don’t necessarily drive fast, I like to get to the speed limit quickly so definitely would have noticed such an odd thing. These were all non-rebuilt all-original Ultramatics.

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I guess I was classifying Type F ATF as an "old" ATF, as opposed to the "modern" Dexrons or Mercons. From past posts I was under the impression that Type F was the best for the Ultramatics, and the primary reason was because the direct drive could/would slip with Dexron or Mercon and was due to the clutch composition, which may be something that I made up in my head.

Brian, in the post you referenced, brought up a couple of interesting points. He noticed a "moan" for the DD clutch under light throttle when using Dexron, which was remedied by switching to Type F. Something that has been reported by others. Presumably the groan is the DD clutch slipping before it fully engages. He also suggested that possibly a smoother shift may be achieved with Dexron because it is more slippery, but maybe that may also cause faster wear of the linings.

I can see where smoother shifting would be desirable, but not if the trade off is a transmission that moans as the DD engages. Is the "moan" caused by an incorrect combination of fluid and clutch materials, or simply the mechanics of the transmission? That is, are Dextron or Mercon, in general, are always going to be too slippery for our Ultramatics? I am currently running Type F with a bottle of Lucas Transmission Fix.

As I work towards rebuilding a transmission for my car, I find this is all very interesting! I guess what I'm trying to figure out is what is ideal for my Ultramatic. Baring any issues, such as excessive wear, should I get a rebuild kit from MM (KIT INCLUDES GASKETS, SEALS, BUSHINGS, AND HIGH RANGE FIBER CLUTCHES) and continue running Type F?

I find that my DD engages quite smoothly, which may very well be due to a "hard", or worn, DD clutch that is slipping more than it should when the DD is engaging.

I'm going to ask MM if they have a ATF recommendation after installing their rebuild kit.

BTW, it is raining in my part of the world, so I'm waiting to go for a test drive to see what I can figure out with my kick down.

53 Cavalier wrote:

I guess I was classifying Type F ATF as an "old" ATF, as opposed to the "modern" Dexrons or Mercons. From past posts I was under the impression that Type F was the best for the Ultramatics, and the primary reason was because the direct drive could/would slip with Dexron or Mercon and was due to the clutch composition, which may be something that I made up in my head.

Bit of a history lesson. The first automatic transmissions simply used engine oil but engines and transmissions have slightly different requirements for an optimal fluid. For example, there are no combustion gases to neutralize in a transmission. But also a transmission does not get as hot, so condensation is not easily boiled off. To fix this problem, GM released Type A fluid, made by GM and Texamatic (Packard used Texamatic formulas). EVERY transmission in those days used Type A; there was no other option (though there were some minor variations/improvements over time). So any difference in lining wear in 50's automatics is NOT due to transmission fluid incompatibility, it's due to the design. Yes the harsh shifts of the Hydramatic and the clutches running away in the Ultramatic occurred with the same fluid and lining materials. Considering this, people tried Type F fluid, released by Ford in 1967, in their Ultramatics. Type F was designed by Ford to give a firmer clutch engagement. This eased the high clutch wear often seen in the Ultramatics (especially in the HRC pack in the TU units).

Brian, in the post you referenced, brought up a couple of interesting points. He noticed a "moan" for the DD clutch under light throttle when using Dexron, which was remedied by switching to Type F. Something that has been reported by others. Presumably the groan is the DD clutch slipping before it fully engages. He also suggested that possibly a smoother shift may be achieved with Dexron because it is more slippery, but maybe that may also cause faster wear of the linings.

I can see where smoother shifting would be desirable, but not if the trade off is a transmission that moans as the DD engages. Is the "moan" caused by an incorrect combination of fluid and clutch materials, or simply the mechanics of the transmission? That is, are Dextron or Mercon, in general, are always going to be too slippery for our Ultramatics? I am currently running Type F with a bottle of Lucas Transmission Fix.

It's important to note that the original cork linings and the modern linings don't have the same coefficient of friction. It's my understanding that cork was more frictive. So even though DEXRON is the correct successor fluid to Type A, it's not surprising that slipping has been reported when using it with modern materials, since Packard engineered a very soft/smooth shift. Obviously this problem will be exacerbated by a transmission fluid change on a rebuilt transmission with some mileage, as the clutches will already have some wear. Note, this is one of the times that a slight increase to throttle pressure can be a large help, as it increases engagement pressures except at full throttle driving. Using Type F with modern materials gives a firm, positive shift. Only if you have a highly original car that is known to have old type linings should you use DEXRON IMHO.

As I work towards rebuilding a transmission for my car, I find this is all very interesting! I guess what I'm trying to figure out is what is ideal for my Ultramatic. Baring any issues, such as excessive wear, should I get a rebuild kit from MM (KIT INCLUDES GASKETS, SEALS, BUSHINGS, AND HIGH RANGE FIBER CLUTCHES) and continue running Type F?

Mostly a question of how much money you want to throw at it. The frugal approach is to tear it down and see which bearings and clutches are actually worn out and go from there. Obviously will want to replace every seal and gasket regardless. Everyone in Ultramatic-world that I've spoken with, who's worth their salt, runs Type F. There's also Type FA if your other hobby is lighting $100 bills on fire, and B&M Trick Shift which is pretty darn similar to Type F in performance.

I find that my DD engages quite smoothly, which may very well be due to a "hard", or worn, DD clutch that is slipping more than it should when the DD is engaging.

Just drive up to a moderate speed (30 mph?) and let the clutch engage. Then punch the gas to full throttle without entering kickdown. The car should accelerate normally. If there is engine flare or an odd sensation (not lugging), then your clutch is slipping. But if doesn't slip during this test then it never realistically will.

I'm going to ask MM if they have a ATF recommendation after installing their rebuild kit.

I'm curious what they have to say as I don't think anyone that works there is actually knowledgeable about these to a decent level, except just the parts in them.

BTW, it is raining in my part of the world, so I'm waiting to go for a test drive to see what I can figure out with my kick down.

P.S. Here is a photo of some relined clutches. From left to right:
9" clutch, Max Merritt
9" clutch, Vendor 'C'
9" clutch, Vendor 'A'
11¼" clutch (appears to be newly lined cork material)

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Spud.

What we need to find are electric sending units for gauges.

Mechanical is more accurate.. ? Which my dad did. Ran tubing to under left front fender. With caps..

And he had gauges on plexiglass. Lines going up fender. Plexiglass / Gauges sat on wiper and he could check pressures.

Electric would be a lot easier. Plug and go.

I have some relined clutches too that I had done sometime in the ‘80s but no idea what they’re lined with. Can one tell from photos?

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The sending units are specific to the gauges so you need to match them. Also, the sending units can be expensive. (GlowShift gets $70 each.)

When I rebuilt my Ultramatic, I added sending units to all six of the external ports. In hindsight I should have added external ports for the throttle and low range too. I was doing this for full time monitoring not just for service type testing. I thought it would be interesting. A sending unit harness connects all six and plugs into a chassis mounted connector. Initially I switched the sending units on and off of the gauge. I hadn't decided how many gauges I wanted. I started with GlowShift digital gauges, but had too many gauge failures. I am in the process to converting to a multi display gauge to have everything on at once.

It might be an interesting project to create the replacement for the PU-300. How many gauges? Digital or analog display? It would have to include sending units and fittings. If someone wanted they could permanently install sending units and then just plug them in for testing.

That might be the thing to follow the Torsion Level Test Box and the Pushbutton Tester. Hmmm.

Thank you all for continued input into the discussion.
As specified in the Shop Manual, I used ATF Type-A, before and after the rebuild. Yes, it is still available here, but without the whale oil. Has worked fine and still does. No moaning or groaning from the DD clutch and reasonably smooth shifts.
During the overhaul we have replaced all seals and gaskets, the input shaft, the upper valve body, front and rear check valve 423547 and 423527. The Governor was checked and deemed functional. Pressure test values were close to spec.
Before the transmission overhaul, the DDC opened on part throttle, when needed. Bug or Feature? I suspect that the rebuild has changed the balance of oil pressures at the DDC Shift Valve. It does not need much, may be just the removal of grime in some passages, or fixing internal leaks.
Will have a look at the Governor again, to start with. Following the overhaul, it's current valve function could be binary, like fully open / fully closed. Sqeaky clean internals and a weak spring could give that effect. The Ultramatic Training manual states, quote "The hydraulic governor is a hydraulic device which delivers a variable oil pressure from the rear pump to the direct drive clutch shift valve, calibrated according to car speed." end quote. This is what is needed.
Will get back asap with my findings.
Cheers, R

56Clippers, I have a PU-300 gauge set if for whatever reason you would want to copy the dimensions of the original.