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Well I felt energetic over the weekend and decided to tackle the seal on the cross shaft AKA gear selector shaft but ran into a little problem of not being able to remove the shaft from the tranny because of frame interference. Looks like a guy could drill a hole in the frame where it needs to pass through to gain clearance but I've just about decided that most of leaking coming from my transmission was due to a very flat, distorted and maybe even reused pan gasket. I didn't go to a whole lot of trouble to pinpoint the leak because I wanted to change the transmission fluid anyway and the Ultramatic Service Manual states that both the cross shaft seal and the throttle shaft seal can be replaced with the tranny in the car but even removing the rear transmission mount does not allow it to drop down far enough for the cross shaft to be removed. So at this point, I've decided to change the fluid and button it back up to see if the leak is as bad as it was or if it leaks at all. Personally, I was thinking that there are a few 51' thru '54 Clippers running around with an extra hole in the frame...or actually, an enlarged hole as it appears to line up almost perfectly with an existing hole located between 2 frame rivets. Now I'm facing the "what transmission fluid do I go back with?" question...the PO said he always used Dexron but I don't know if it was the III or VI. I read somewhere that Dexron VI does not suffer from viscosity breakdown like the III did so maybe it's at least equal to the Ford FA fluid.

Dexron-VI
Dexron-VI was introduced in 2005. All Dexron-III licenses expired permanently at the end of 2006, and GM now supports only Dexron-VI fluids for use in their automatic transmissions.[3] Fluids asserted by their manufacturers to meet Dexron-III standards continue to be sold under abbreviated names such as Dex/Merc and D/M, but since the Dexron-III licensing system no longer exists, these fluids are not regulated by GM.[citation needed] The use of previous fluids can damage transmissions meant to use Dexron-VI.[3]

Decisions Decisions...

Based on my own experience and that of many other owners, I'd use Type F fluid which is believed to be the closest in formulation to the original Type A. Note that many users have also had good satisfaction with B&M's "TrickShift", and yet others have apparently had no problems with Dextron.

When you remove the pan, check it to see if the bolt holes have been distorted from prior overtightening. If so, use some flat steel and a hammer and tap the enlongated portion of the bolt holes back to a flat surface.

Too long ago to remember how I did that seal on my 54, but I do recall it was a simple job, removed the lever, drilled two small holes into the seal, inserted a couple of short sheet metal screws for leverage, and just pulled it out.

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Yep Owen, you're right...seems to be a mixed bag of opinions on the various fluids when it comes down to performance and operation...the pan was checked for distortion and the mating surface trued up before it went back on. I placed a bead of red silicone on the pan and "set" the gasket then turned it over and left a heavy weight on it overnight.

Unless the '54 frame is different from the '53 I would have to use an angle drill to punch those holes 'cause a straight drill won't fit between the X frame and the tranny.

Gator -

Type F was Ford's replacement for Type A/AQ-ATF, but designed with their own transmissions in mind. GM kept using Type AQ-ATF well into the 1960s, then replaced it with Dexron. Now, I'm no engineeer, but because successive formulations of Dexron no longer contain whale oil as a friction modifier, and I suspect that it may no longer be as good a replacement for Type A as it once was.

Read the Fluid FAQ.

However, I wouldn't use Dexron VI in anything other than where mandated as such by the manfacturer of the transmision. It's a synthetic fluid that's not only expensive, but not needed in earlier transmissions. Why waste your money on it?

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I know...I've read it and others as well and It's like every other subject that one might seek an opinion on BH...you ask three different people and most of the time you get three different answers. Pete Fitch of Ultramatic Dynamics suggested the Dexron VI stating that it's backwards compatible with just about everything...I personally don't like synthetic fluids of any kind but again, that's my opinion and perhaps I'm just too "Old School" to change or just too old period but I'm more in Favor of the Type 'F" than any of the Dexrons or DexMerc's or Mercon or any combination thereof.

Gator -

Thanks for the additional info.

My FAQ wasn't intended to be entirely conclusive, but can't be as I don't know of any supplier doing lab tests using an Ultramatic. It's merely meant to show that either Dexron or Type F will work, though they have somewhat different properties. Given the available info, the choice depends on what friction material are in your unit and how it behaves.

While I'm inclined to use synthetic wheel bearing grease (next repack), I just don't see sufficient advantage to synthetic lubricants for engine, transmission, and differential in antique autos.

Admittedly, synthetic fluids do last longer, but I've found them to be more prone to leak in vehicles that weren't designed with a synthetic product in mind.

I had a recant fluid change ,using as close to the recommended fluid as I could find ,recantly I topped the ultramatic up with some lucas anti slip fluid ,wow what a difference ,It works better but I couldnt tell you how.I also have a shift selector leak ,but its not so much fluid actually comming out .A pint is 3 square feet I hear