Packard Forum Index » V-8 (1955-56)

has any one had this problem with torque converter clutch wont release until hot .and even then it hangs on till almost stoped .also locks up imidiatly after high gear shift . late 54 gear start just rebuilt .ive done and checked every thing i know to do .need help.

I suspect that your governor is jammed, although it may be another related valve in the valve bodies. If you have access to a hoist, You should check the direct drive piston pressure. If it comes up as soon as your tailshaft starts to turn it is more than likely a jammed governor. Look up "troubleshooting in the Twin-Ultra notes.

As a first step it would also be prudent to contact the re-builder of the gearbox, before you attempt to dismantle anything. He may be prepared to check the problem out.

PT

thanks for your reply, I am the rebuilder ,removed cleaned and replaced valve body and governor twice all valves work very smooth. converter clutch releases good on work bench during air test. thought maybe input shaft walk covering apply and release passages at bushings was the anwser ,tried to simulate on bench but released perfect every time.

Once had a direct drive disc stick like crazy til warm because I forgot to cut the chamfers on the relined disc. Was quite OK when warm but would stall the engine every time when cold.

56 units are notorious for running the low-high and direct shifts together unless accelerated vigorously; usually 54s have wider shift separation. I am wondering if some of your valve body springs might have gotten switched around. In any event it seems that the spring in the direct shift valve is too weak. When does it make its upshift?

Peter is right, it would be good to check the governor pressure, and also the direct drive pressure and the convertor in pressure. The convertor in pressure actually pushes the direct drive piston back to home when the direct is supposed to release. If it is somehow slow coming up the direct disc can drag.

Ross thanks for your reply. Im the one who called you last night sorry for the interuption but im getting a little desperate here. i rebuilt this trans on referal because i have a good reputation on more modern units.i understand this trans is troublesome, herd it said bad desighn. i think you may be on to something with converter in pressure i noticed a pressure leak into direct drive port on bell housing while applying air pressure to converter in on bell housing.seems to be leaking from front pump bushings which i cannot find. the clutch wont engage from converter in with air pressure.40-80 psi but the clutch will lock if i put air pressure to converter out port on pump. i suspect cross leak at front pump bushings. I would like to call you again if you dont mind, every one i talk to says ask you. thanks for your help.

does any body else have any ideas the expert wont talk to me on the phone or reply to the forum topic any more. I guess I will call Peter Fitch and see if he is nice enough to help .

The front pump bushings replacement is extremely critical on rebuilds, as little as ten thou combined wear between shaft and bushes will result in a "potential to slip" High Range and DD Clutch assemblies. However your problem appears to be more of a pressure monitoring/sequencing/valve body problem than a bush problem. The supplement to the 56 Twin ultra overhaul notes includes the dimensions and details of all of the springs and valves in the bodies, because it is extremely easy to put them in backwards, or a spring into the incorrect body orifice. The bodies come off easily from underneath without removing the box. It is extremely important to use the correct inch-pound torque on the valve bodies, as incorrectly torqued valve bodies was a constant problem when Ultra's were returned after warranty replacement. I would first check the DD pressures and High range clutch pressures. if these are within manual specs, then your front pump bushes and shaft are ok. Governor pressure reading is a PIA, especially with the PB motor but it will let you know what the governor is telling the rest of the box. PT

what about, end play?, reactor end play?

Like any other businessman I can talk about Ultramatics during business hours and not when I have a house full of guests who are waiting for dessert to be served.

If I am not around, and as a one man shop I am often in and out for errands or test drives, you can leave your number on my machine. I do not carry a cell phone.

As Peter mentions, The fit between the front pump bushing and the input shaft is highly important. Also, that bushing can be installed incorrectly or conceivably spin in service so that fluid passages are obscured or blocked. I am pretty sure Kanter has them, or if they are out I have some 55s which I am almost certain is the same. 56s are not.

thanks to all who have replyed I have the trans back on the stand so I cant check pressure, but will when I reinstall if the problem persist. The valves and springs are in correctly per service manual,the book i have has spring lenght,diameter and number of coils for each valve. the first thing I tried was to remove valve body to check for a sticking valve but they all work smooth will fall under there on weight in bore. I found a tsb to check direct shift valve spring retainer there easy to pinch between valve body and end plate. it was pinched corrected and no differance.removed governor checked and re cleaned valves.no differance. the thing that gets me is sometimes it works perfect shifting and unlocking and then shifts eratic to quick and to hard for amount of throttle.the little screw on valve body at throttle valve that your not supposed to adjust is screwed all the way in ,every picture ive seen has some space between screw head and locknut. could this be right have any of you seen this screw all the way in before.the stator shaft which is supposed to have .010-.017 end play is a little loose at .023 but the thickest .110 thrust whasher is installed. is there another way to tighten it up or is another converter needed. I did find the pump bushings at max merrit they dont advertise them but do have some in stock th sales man said it is one tall bushing that takes the place of the factory 2 bushing set up. i questioned him about the fluid passage being blocked with one bushing he said it has two holes drilled in it at propper location. Ihave ordered a new input shaft to use with this bushing hope it works. I also wonder if it is correct for this trans to down shift to low only after complete stop, not counting kick down.