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Have you checked for excessive rear end gear lash ( as I suggested above) or for a loose U joint??

I haven't checked excessive gear lash. I didn't think it was a problem because I have tend to not have the problem when the transmission is cold - when I first start it and back up in the morning the shift has been just as soft and gentle going into low or reverse as when going into high range. It only "clunks" after I have driven it for a while.

Anyhow, I have more to do to get the differential pinion seal and the rear transmission seal replaced, as well as the transmission and the oil pan gasket, as it weeps from all those places.

Am I right that the right-hand side adjuster on the transmission is for the reverse? That's the only one I was able to adjust, given the time I had.

Gosh, by the way, it is SO HARD to check the transmission fluid. Probably the only way to both safely and accurately check it is to put both the rear tires up on "blocks" and both the front tires up on jack stands, so you have the thing up high enough to get under there, but still level. Even then it is difficult.

I really would like to be able to double-check things, say on Sunday morning before I take it somewhere, but the time (and getting dirty quotient) required basically precludes that.

But thanks, Fred, I will check the gear lash more thoroughly next time I get to look at it.

The rear adjust nut is the reverse band.

Back in the day most Packard owners didn't mess with the dirty work and dealers or a service facility took care of all that when the car went in for its oil change and grease job. Getting to the dipstick was not a problem with the car on a lift.

I still think the flexible tube and dipstick thru the cap is the most viable option for something that should be fairly easy to do and would give a dipstick that could be checked from the engine compt.

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I've also thought about using a generic dipstick extender, but how does one calibrate the the reading to the ultramatic?

Les

If you use the cap approach you would drill out the rivet and remove the original dipstick. Make a hole and mount the new dipstick tube in the cap. Once that is done and dipstick is inserted and seated in what will be its normal position then take the old dipstick and lay it along side like it was originally positioned in the cap. Use the marks on the old dipstick to make corresponding marks on the new dipstick. The Jegs item has some marks but the instructions say new marks can be custom made as needed. Advantage to keeping the cap in the conversion is with a flexible tube the cap could still be removed per usual if you ever wanted to take advantage of the large fill opening.

In the event you ever wanted to revert to original, by removing the tube and covering the hole with a sheetmetal plate between the gasket and cap bottom the old dipstick could be riveted back on the plate and cap reused per original.

Unless there is a large visible leak from the trans it's not necessary to check it weekly. If it were now 1953 I don't think you would take it to your local Packard dealer every week before your weekend drive.

I drive a 2002 Grand Marquis with 150,000 miles. As long as there's no puddle or wetness on the back bumper I check the trans only every 3 months....and never need fluid.

Just drive your car and enjoy.

Thank you Fred. You have to appreciate my paranoia as if the transmission were to break from my negligence it is obviously an involved and expensive thing to rebuild!

So after adjusting the right-side adjuster, and thinking about it a little, I believe I probably adjusted the low-range band and not the reverse band. Probably the reverse-band adjuster is on the left-hand-side.

Reason being - reverse clunks just as before, but low-range clunks now, too!

So that is hopeful. Perhaps I just need to do the adjustment (correctly this time) to both adjusters (on the left side and the right side) and I can get it right.

Not sure whether I accidentally tightened it too much or too little - any thoughts as to which would cause it to "clunk". My thought is that it is probably not tight enough.

I found that the locknut didn't move too smoothly on the adjuster screw, mostly that was crud, which I did my best to clean off while I was underneath the car. Can I take the adjuster/locknut completely off so I can clean it up off the car? Or would that can something to come off inside the transmission?

Removing the adjusting screws on the 49-54 trannies is perilous as the band struts can fall out and it is miserable to get them back in with the unit in the car.

Use a small wire brush to clean up the threads as best you can and then using two open end wrenches back out the locknut a few turns before you begin the adjustment. You don't want drag from the locknut affecting the torquing of the adjuster.

After the screw is tightened I put a dab of paint on a corner of it so I don't loose track of the 1 3/4 turns out, as that is accomplished with an open end wrench. Lastly I tighten the locknut while holding the adjuster still.

The rearmost adjuster does reverse, the forward does low.

Packard used a very elaborate two stage piston in the low and reverse servos to insure smooth application. This was particularly done to allow rocking the car in snow or mud to get the car free without beating the trans to death. That feature works quite well. If there is not excessive play in the driveline there is very little to notice when shifting.

Dear All (but especially Fred),

Sorry for all the questions.

I checked and I have about 10 degrees, maybe a little less, of rear end lash. I can see and feel play in the differential gears.

That might be it. Seems like a little more than it should be.

I had a leaky pinion seal and I had it refilled at a Speedy Oil Change because I couldn't get the fill nut off myself, it needed an air wrench. They told me it was only a little low.

The symptoms of the "clunky shift" are these:

1. When you first start the car and before the transmission is warmed up it shifts very gently from High to Low, from Low to Reverse, from Reverse back to Low, and from Low to High.

As the transmission warms up the shift from High to Low and back is still reasonably gentle, though perhaps the shift from High to Low is a little clunky. The shift from Low to Reverse and back is where you hear and feel a "clunk".

I checked and the band I adjusted was the rear-most one, e.g. for reverse. The rear-most one is on the passenger side, the forward (e.g. low-range) one is on the drivers side.

My thought is that band adjustment might make both of these shifts a little softer, but since they are soft and good when the transmission is cold, it would seem that it is not the band adjustment that is the primary thing. Also the fact that the shift from High to Low Range is reasonably soft.

But it seems perhaps it could more be a function of the differential gear lash?

When I got this thing running after around 10 years of sitting, I noticed the transmission was low. I put "Type F" in it. Ten years ago when my Dad and I were driving the Cavalier around (back when he was still alive) I had put Dextron II in it. So there is a mix of Type F and Dextron II in there (maybe even something else because it never was drained fully).

So it is a possibility that the symptoms are exacerbated by the fluid change/mix from Dextron to Type F?

What I am planning on doing is changing out the transmission fluid. I got a new gasket (and new transmission rear seal) from Kanters. The new gasket should also make the transmission reasonably fluid-tight, I hope.

From what I read the Type F should be "better" than the Dextron II, more compatible with the clutch material and probably a little bit more viscous than the Dextron II. So I probably should just put all Type F in it. But it makes one wonder...

Finally, does one think a competent rear-end shop could rebuild the differential on my Packard?

Thanks and Sincerely,

Jerome Solberg