I have a 2002 Xterra 4wd with the P0744 code. I drained the pan and checked the resistance on all of the solenoids on valve body and they were good according to repair manual, I ran 12 volts through them and heard them moving inside, replaced filter and fluid and added lucas oil additive. Didn't fix my problem. In drive, it won't shift into third or fourth and slips out of second when I don't accelerate slowly, but shifts perfectly fine when I manually have it in second. All of this happened after I cleaned the throttle body, replaced the TPS, and had the dealership recalibrate it. My transmission was perfectly fine before I messed with the throttle body. Also, when I dropped the transmission pan, the fluid was dirty and smelled burnt and the magnet had a magnetic sludge on it.
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