T-407/TF727 Variations and Parts Differences

It mounts to the rear of the case, not directly to the engine. That portion of the case is the same for all applications.
 
Scott, you're right about the parking pawl rod deletion and that is because the compounder unit replaces the normal tailshaft housing, which also necessitates the drum brake. I'm curious about the interface between the trans output and the compounder. I wonder if a special output shaft is required along with matching planetary gears? I'd love to have a good look at one of those units separated from the trans. An exploded view would also be cool. I imagine the damn things are basically hens teeth, so that likely falls under the category of wish in one hand, poop in the other. If somebody reads this and has one, please, by all means, post some pics from all possible angles. Hell, tear the damn thing apart and rebuild it in a special build thread. I'm thinking this unit might possibly be the source of all those fairy tales that have been bandied about for decades concerning the mythical low gear sets that supposedly "came installed" in some heavy duty 727 units...and yet no one has seemingly been able to produce conclusive evidence that they actually exist. This unit does provide a low first gear, but it sure as hell isn't in the form of lower gears inside the main case.
 
Sorry been busy (surgery, recovery, trying to get projects out of the upcoming rotten weather, etc) I had 2 of those trans and the compound gear worked like a split ratio (2 speed) rear diff. It would start out in compound low, then c2, c drive, then the compounder would lock and it would go to 2nd gear then drive (you could run 1st locked but it was almost the same ratio as drive & compound)
one I had was in a dodge 5 ton chassis motorhome ('77) and the other was in a '77 IH 1 ton with amc 401 (aka IH 400) both were canadian models
the compounder was simply a planetary with a band and just the reversal of the current o/d units use in dodge and Jeep mopar o/d trans.

How common was the allison 540at down here? I saw a couple behind 345s in candian junkyards over the years (I got one, scored a mopar bell and put it in my buddy's '61 fargo w800 5 ton when he lost use of a leg in a motorcycle accident)
 
I have a a727 out of a '75 Scout which we are rebuilding. This transmission has been opened and messed with by someone before I got it. The accumulator spring is missing, does this model have one? 2nd question: is the kick down servo on this model usually the controlled load version without an inner spring?
Thanks
 
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