I just finished rebuilding the 360 in a 1999 Dakota. We used a scan tool to sync the base timing and it fired right up first try. Runs great, no leaks. Took for a test spin seemed sluggish like taking off in high gear. Hooked scan tool back up and it does show trans is stuck in 3rd gear. Has all of these error codes. Tried to clear them but they come right back.

Odd thing is transmission was not touched. It was supported with trans jack during the rebuild of engine. Didn't touch anything on the trans other than bellhousing and torque converter bolts.
None of these issues or codes were present before engine swap.

How would doing an engine swap cause all these transmission codes?

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1963 Belvedere 440 Max Wedge Tribute
1970 Charger R/T S.E. 440 Six Pack
1970 Challenger R/T, 528 Hemi
1970 Charger 500 S.E. 440 4 BBL
1970 Plymouth Road Runner 383
1974 Chrysler New Yorker 440
1996 2500 RAM 488 V-10 4X4
2004 3500 Dually Cummins 4x4
2012 Challenger R/T Classic.