WTF are these people thinking? Are you supposed to stick your finger in there to feel for the 1/2 inch? Must have been some screw-up somewhere along the way. "Fill it till it overflows" is supposed to be the standard procedure, isn't it?
That was how it was originally intended to be... Fill to the hole.
A little TR3650 history here...
Upon release, the TR3650 was plagued with notchy/clunky 1-2 shifts when cold. they made change after change to the internals attempting to fix this. These changes made the second gear engagement more aggressive by redesigning the second gear, the 1-2 synchro hub and the outer blocker ring for second gear.
There are many posts about installing the "TSB upgrade" kit.
It seems that even with all of these changes the problem was not solved. In the end, they stated to fill the TR3650 to 3.0 Liters of fluid (not Quarts).
The present second gear repair kits include a sticker to go on the transmission stating the 3.0 L fill.
This lowered the fill level stating that the transmissions had too much fluid in them all along.
All of this happened before the 2005 models were released. For 2005 the TR3650 is very different from the previous years. The entire case was redesigned and the lower fill plug was incorporated in that design.
Now, how did I learn this, and where is the documentation? I've looked around and haven't found much at all. I will keep looking.
I got most of this from conversations with Tony at Astro Performance over the years. He was the one that pointed out to me that the 2005 had a lower plug as I recall.
...and guess what! If you put those two tail housings side by side you can see that the fill plug is positioned at a lower spot than on the previous version.
Perhaps I can post pictures later. I have both tail housings sitting around but they aren't handy for a picture at the moment.
Now for a 2009 Ford Shop Manual to make the blanket statement does raise the question. Does that manual differentiate between the two designs? I don't have a service DVD newer than 2001.
None of the shop manuals I've downloaded from Tremec's website show anything about the changes for 2005 and up.
The bottom line is that filling with 3.0L should be correct for both transmission designs.
LOL:
The Pinky Finger makes a pretty good dipstick, but one can fashion something out of a piece of bent wire. Just make it long enough that you can't drop it inside the transmission and lose it like one guy I know did... (It wasn't me...)
I thought there was a TSB that said to fill to 3/4 inch below the fill plug... But I can't seem to find it... Only the reference to the 3.0 L spec.