Originally Posted by Mark Kovalsky

If you are going to do a complete fluid change, also called a flush, you must use a heated flush machine. There is a thermostat in the trans that will bypass 90% of the fluid to the cooler if the trans is cooler than 170°F.

Originally Posted by MWILLIAMS

Thank you very much. I will check my stick also. The local Ford dealership is telling it will be between 300 - 400.00 to flush the tranny and change both filters and the big cost is the fluid. I wonder if they are putting gold in it.

Originally Posted by bubster1997

If you go to a local mechanic shop next time, the cost will be around $100. You could even get that price at say a jiffy lube.

Originally Posted by 1973Ford2004

According to my 2004 manual, Mercon ATF for the 4R100 (4speed) which is what I have and Mercon-SP ATF for the TorqShift (5speed) I'll type the warning it's long and is probably adding to your confusion, but I'm shortening it

"Ensure the correct fluid is used. Tranny fluid requirements are on the end of the dipstick. Dual Usage are not to be used in tranny that requires only MERCON fluid, but they can be used in tranny that requires MERCON V.

Do not mix MERCON, MERCON V and MERCON SP

There's more but I'm sure you get the point, I never knew it until now but check the dipstick, lol now I've gotta go check mine just to be sure it's true