My truck is a 53 half ton panel with the 4 speed, still have the torque tube. I swapped it out for another SM420 because of bearing issues. It works well, except it doesn't want to downshift from 4th to 3rd unless the truck is going less than 15 mph. Downshifting into second is not possible unless I'm at a dead stop. What should I be looking for?

1953 Chevy Panel
In the Stovebolt Gallery
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