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1970 TH400 - No Downshifting Into 1st Only

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Old 04-06-2024, 03:54 PM
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harrydunn
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Default 1970 TH400 - No Downshifting Into 1st Only

Transmission shifts beautifully 1-2-3 and back down 3-2-1 when coming to a stop. Kicks down from 3rd to 2nd when gassing it a bit but will not kick down to 1st from either 2nd or 3rd at any speed up to 25 mph or so. Used to work just fine a few months ago. I believe line pressure is enough for a 3-2 kickdown but you need a properly functioning kickdown switch at the gas pedal and a properly-functioning kickdown solenoid on the trans to get a kickdown to 1st? I've tested the solenoid at the transmission with 12v and I get the click. I reach up under the dash and engage the kickdown switch manually (with key on) and also get the solenoid click at the transmission. Perhaps the trans solenoid is clicking but just bad? Not a problem for me to drop the pan and replace. Have dropped many pans. Thanks!
Old 04-10-2024, 03:27 PM
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harrydunn
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Disregard. Figured it out. Despite thinking I had the gas pedal switch adjusted correctly, I did not. I "reset" it and it does kickdown to 1st now. Sometimes, it will stick however and I have to "reset" it. again Will try to lube it a bit. Not a big deal as I rarely kick it down to 1st gear.

--Mark



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