Auto Parts: transmission swap, gmc 1500, piece case

Question
QUESTION: what transmissions swaps with a 1997 gmc 1500 4x4

ANSWER:      They use the same transmission in '96 and '97, although even then they have two different units.  One is a two-piece case and the other is a one piece case.  So, any Chevy or GMC 4WD with the same engine should swap out .

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QUESTION: My engine is multi port does it have to be a multi port engine to make the transmission work or can the engine be throttle body

Answer
    Your engine and transmission are both electronically controlled.  The new transmission, if it didn't come from the same type of engine, might not behave correctly with your computer.  GM OBDII computers can be reprogrammed, but the software is expensive and most shops will charge around $500 to do it.  Yours might need a custom program, so the price would go up.  Much better to spend the money on the correct used transmission.