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  1. TH 400 4BD1T Swap help

    Transmission, Adapter, Transfercase Discussion
    I am finishing up my swap, 4BD1T to a TH 400/NP 205, and I need help with the vacuum modulator. Allegedly, a TH 400 that was connected to the 6.2L diesel motor from the factory & the CUCVs had some sort of vacuum source that modulated the amount of vacuum needed to shift normally. This set up...
  2. 4L80e: Hard shift between 1-2

    Transmission, Adapter, Transfercase Discussion
    Just got my F150 project running last thursday the 8th. I'm running a '93 4L80e with an Optishift controller. Now when at light to mid throttle, the shifting between all the gears is nice and easy almost not even noticeable...but at full throttle, the 1-2 shift delays a bit then kicks like a...