I am just about to do the line valve mod and was making sure I had the right trans fluid (still not sure whether to go with Mercon III or V) and then started thinking about the filter. Nobody is talking about changing their filter when they change the fluid, How come? Does the filter not need to be changed out every 15-20K mi? Seems silly to change the ATF and not the filter too. What am I missing? If you need to change the filter,where can I get one? Thanks, Jeff

 

The filter does not have to be changed for aprox 50000 miles (unless you change to a 4X4 pan. You can purchase the filter from your local Ford parts department. Check your trans dip stick, if it says mercon V use mercon V. All the Ls I have seen have Mercon III in them. Do not mix the fluids.

 

Change the filter. You are in there and the fluid is out why not. It's cheap insurance. I change mine about every other oil change. Clean fluid will help extend the trans life.

 

You're not supposed to put Mercon V in the 4R100 transmission. Only regular Mercon.

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It gets regualr MERCON, not MERCON V. Go ahead and change the filter, if you have the deep pan, go to AutoZone and ask for Deutch TF 325, it's the same as the dealer part and half the cost. For the regular pan I think it's Duetch TF 350, but not sure on that one.

G