SUPPLIES / EQUIPMENT


-approx 4-6 jugs of the correct fluid for your transmission
-two lengths of neoprene line (same size as your trans cooler steel lines / approx 24" each)
-two mini clamps or tie straps
-compression union to join steel cooler lines (if req'd)
-one 3-5 gallon white pail

PROCESS

-Disconnect one cooler line at the radiator or cooler. If unable to do so, using a line cutter, cut the steel cooler line in a place that it can easily be rejoined with a compression union
-attach length of neoprene line to each, secure with a mini clamp or tie strap
-hang both hoses over the bucket (keep a hand on em for the next step)
-have an assistant start the engine and allow it to idle only (do not rev or put in gear)
-fluid will come out of one of the hoses, allow engine to run until flow starts to slow down or fluid becomes aerated, shut engine off.
-pour contents of one 4-5ltr jug of fluid into the trans
-fire up engine and allow to idle again, shut off as above.
-repeat until you have clean fresh fluid coming out of the hose
-hook line back up or rejoin with compression union
-top off transmission, cycle between drive and reverse, recheck fluid and add just enough to bring between full and add mark.
-shut off and recheck line for any leaks
-done.

The above applies to a trans with a dip stick, mod'd version could be made to work with one with a sight / level plug such as a later model GM or similar.
Unlike a flushing machine (several OEM mfg's now caution against using them), have yet to see any ill effect from doing the above.
With transmissions rebuilds costs increasing due to complexity, cheap insurance you'll get the max life out of yours.