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727 kickdown



I always thought that my '73  WM's tranny- which I think is a 727.. was fairly
unwilling to kick down.  It would do it, but it certainly isn't what you'd call
hair trigger.

So when hauling the trailer the other week, on the steepest hill, we were
going 60mph, in high, with my foot to the floor.

Now the speed was acceptable, and my wife looks unkindly upon 
experimentation with a loaded horse trailer, so I didn't try kicking the
pedal or anything.  I thought that maybe a downshift at that point
might do little more than overrev the motor, which is why it didn't.

But, I have now calculated that with 31's & 3.73's we were only doing
a little over 2400 rpm.  If the 727 is the same as the Scout version posted
on the BB web page, 2nd gear would kick it up to 3500 RPM, still withing
acceptable limits.  So I think it should have downshifted.

Furthermore, looking at my HP curves, I discovered that I would see 1/3
again as much HP at that higher RPM... making all those diesels eat my
dust!! <g>

So--
1) How does the kickdown actually work?
2) Is there some RPM limiting in the system (Somewhere in the mid-70mph
range I think kicking down is a BAD idea)
3) Don't you think my truck should have hit the passing gear in that situation?


**In Use**
'70 1200D 4x4 Travelette 392 4spd
'73 1210 Wagonmaster, 392 auto
**Prepping for Repaint**
'67 1000B step-side p/up  BG241 + 4spd
**Parts (future projects?)**
'72 1010 T'all  392 at, '67 1000B T'all 266 3sp, '68 1100C 4X4 T'all 345 at






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