Somebody please help. I thought changing the tranny fluid would be cut and dry. Holy Crap!!! I've called all my local Ford Dealers and all the good Tranny shops in this area to inquire on a "Proper Tranny Service". I've gone 360 and still don't know what to do. My 04' Exped. has 40k and I've been told every scenario and condition to consider. The Ford places want to flush without dropping the pan with either a BG(chemical treatment as well) or MOC flush machine for around $160(220+ for flush/pan drop). The tranny places say to drop pan/change filter/flush for a complete exchange and charge $125-150 for everything. One place has a machine but says he recommends an "old school" service. He said tranny fluid functions more as a hydraulic fluid and says older fluid with clean filters is definitely better than clean fluid and clogged filters. He modifies it some by using a straw device to run down the dipstick hole to suck out more fluid. Crank truck for few seconds and does it again. Says he gets b/n 8-9 quarts vs just a few with dropping pan only. This is done before pan is dropped. Downside to this is that I've heard air can be introduced into the system and muck-up things somewhat. I know this has been beaten to death but just curious if anybody has any good recommendations that can make one choice more logical. Are flush machines potentially that bad? Do the newer trannies have to be flush to get 150-200k miles or is filter changes/add back fluid enough? Would love to hear some Ford techs chime in here(and be very honest of course)

 

That's my choice - but just do an exchange with a machine to hold the fluids using the tranny pump to do the work, and without using flush chemicals.

 

I agree completely.

 

Thanks guys. The shop that made the most sense uses a MOC machine that connects right into the tranny pump intake. He said it exchanges the fluid naturally thru the tranny and is more efficient than BG's system which connects to the tranny cooler lines. I'll have to take his word for it b/c I'm never seen either machine up close. Plus he drops the pan and changes the filter(which Ford doesn't want to do) and doesn't use solvent solutions before flushing. I appreciate the replies on this...