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47re trouble shifting from 1-2

11K views 12 replies 7 participants last post by  mathews8pt 
#1 ·
Lately ive been having issues with my
Truck shifting from 1st to 2nd, i have to
Let off and get back on the throttle lightly
For it to shift, i had the local shop drop the
Pan and change the governor solenoid and
The transducer and it still wont shift right,
What am i missing
 
#5 ·
You must have done other things aside from the speed sensor or the speed sensor changed the gov solenoid signal because the 2nd gear shift is hydraulic in the VB. The truck has zero electronics for 2nd gear, only the governor pressure sensor.
 
#3 ·
tranny speed sensor on left side of extension is very possible. Also adjust 2nd gear band if not done with internal sensor replace.
 
#4 ·
BS, the transmission doesn't give two ..... About the speed sensor for a 2nd gear shift. Its all hydraulic in the VB.

It is most likely gov solenoid or more than likely the intermediate band needs adjustment.
 
#7 ·
Did your speedo work properly?

Here is why I say that, when I built my transmission there is no electronic control over the 1-2-3 shifts. There is only hydraulic pressure which is governed by the electronic governor. TCC lockup and overdrive have solenoids. You can move your 123 shift points around solely by adjusting your tv cable...

So maybe your speed sensor was causing the governor to change line pressures causing a hang shift without seeing the tv movement to overcome it. But the speed sensor doesn't have direct control over that shift.
 
#9 ·
Mine did same thing the band wound up breaking in half when I had this problem

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#10 ·
A rise in governor pressure (electric controled) vs throttle pressure causes the 1-2 shift and the 2-3 shift. The trans speed sensor is what allows governor pressure to increase. The vehicle speed sensor (at rear axle) is a input also but perhaps contributes more at higher speed for TCC and OD engagements.
 
#12 ·
There is hydraulic pressure governed by an ELECTRONIC governor sensor. Something about that just doesn't make sense. If its electronic, it wouldn't make you think it's solely hydraulic, right?? I'm no expert though.


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#13 ·
A faulty speed sensor will cause all kinds of wierd problems, trust me ive been through it. Its not always the cause, but @ $20 its easy/cheap to try.

I would get a scanner on it if possible to see if the new gov sol/trans. is bad(does happen) and check the front band as well.
 
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