Bought a 4WD hummer lq4/4l65e with goals of selling and buying a new rebuilt 4l80e. Didn't get any good offers and everything in combo was so low mile/clean decided to
do the swap with help from people on here and ls1tech and videos on youtube. First time in a trans. Wil lbe stock to stock+cam build.
TEARDOWN - not going to take as many pics and rebuild will be a video. Its well documented - but here are the steps and some pics.
Assumes mostly transmission is upside down with input to your left and tail housing to you right.
STEPS
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Remove external like vent tubes and shaft selector electronics on side.
Level trans tailshaft end with 4x4 or similar so pan is near level.
Remove pan and gasket - 13mm from memory around 12 bolts.
Remove 2-4 servo on sde. Get a soft hammer and tap and remove snap ring. Place locking pliers on lip of cover an pull out - get a pick and pull up on oring until it thens out enough whislt pulling pliers till assembly removes. Remove entire assembly (3-4 pieces and apply pin etc and bag).
Disconnect all wiring harness tabs you can see carefully with screwdriver.
Remove retaining clip on the Pulse Width Modulator which sits on top of the TCC solenoid on bottom left corner near dickstip hole. Its kinda tricky I used a pick and then a screwdriver. Remove PWM and retaining clip and bag.
Remove 2x10mm bolts on TCC holddown and bag. Twist and pullup TCC and move it over to the side of case (flip and hang).
Remove Detent spring by shift lever on top - 13mm.
NOW VB
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17 bolts total. 3x8mm on lower right by rear shaft. Rest are 10mm. 3 on top of the manifold pressure switch are longer. The bottom 2 on same switch remain.
Lift VB carefully and slowly and turnover and place in pan.Remove manual link or if it falls bag it.
Remove 7 checkballs with a magnet and bag.
Remove 3x10mm bolts on 3/4 accumalator housing in bottom right. Hold main gasket near edge and tilt/pry off and remove and bag.
Remove stiffener plate - 3x 10mm bolts and bag.
Remove seperator plate and the 2 gaskets (1 each side) and place in pan.
Remove the #8 checkball near the 3/4 accumulator with magnet and place with others.
Remove the 3/4 accumulator piston spring, then gently rotate and pry on the piston using the pin by rotating and rocking. Had to remove pin to let air vacuum out but then came ok. Bag.
Remove wiring harness by pusing the connector through the transmission whilst gently pulling on wiring harness. Or use a large socket. Dont brake teh retaining clips. Bag.
PUMP and Iput/Reverse Assembly Removal
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Remove the Pump by gently prying on inside of the case - you will seea few points - keep it even and gently pry out whilst supporting and pulling with other hand.
Mine had the case outer seal - removed that with a screwdriver.
Relaxed the band by prying against it with a screwdriver - band is now seperated from anchor.
Pulled the input/reversinput drum ut by hand whilst supporting.
Remove the Band.
Remove the band anchor.
Some pics.
