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72 passing gear

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Old Mar 14, 2022 | 03:14 PM
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Default 72 passing gear

72 with TH 400 The kick down to a lower gear for passing works fine as long as you are below 50 mph. Above 50 mph does not work.
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Old Mar 14, 2022 | 05:42 PM
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Originally Posted by Dave Witman
72 with TH 400 The kick down to a lower gear for passing works fine as long as you are below 50 mph. Above 50 mph does not work.
Have you verified that the pedal is in contact with the kickdown switch?
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Old Mar 15, 2022 | 09:19 AM
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Yes works fine if below 50 mph.
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Old Mar 15, 2022 | 09:45 AM
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Did you actually get under the dash to move the pedal with your hand to see if the pedal loses contact with the switch?
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Old Mar 15, 2022 | 08:44 PM
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Depending on your gearing that might be working fine. Based on a lot of stuff (governor being the main, vacuum, line pressure, and a bunch of other stuff I don't know about) the kick-down won't operate at higher engine rpm, basically not wanting to shoot the RPM up to 4000 when it's already at 2800-3000 by dropping the car into second (let the secondaries on the carb do the work

There is a chance there's a weak solenoid or ??? but start with the upshift point

Stick your head under the car with it not running (key in run position) and have someone press the gas to the floor and you should be able to faintly hear the click of the solenoid on the trans. If you don't hear it, manually press the switch at the gas pedal
From a stop if you give it full throttle (kick down is engaged) the RPM that the engine upshifts from 2-3 would be pretty much the highest that it would allow the transmission to downshift at.
M
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Old Mar 15, 2022 | 09:54 PM
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The kickdown pedal to the left of my brake pedal works every time, though I have to also select the gear manually with my right hand.

Would a B&M shifter let you manually downshift with an auto?
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Old Mar 24, 2022 | 11:14 PM
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ok update I replaced the kick down solenoid and it works all the time now. I believe the old solenoid was weak and would quit working when trans fluid warmed up. Had the old solenoid on the bench and it would work for about 4 cycles before it quit.
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Old Mar 25, 2022 | 11:27 AM
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i had a pontiac catalina convert i got for 300 cuz it had a bad trans. it was the other way around. the ball the kickdown solenoid was hung up and didn't close the hole to allow the upshift to 3rd. sold it for 700 and thought i made a killing... that kickdown is the first place to look with shift issues. it is also the cheapest and easiest fix.
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