96 ranger 4.0 automatic 4x4. 4r55e...
I read online that I needed mercon... The fluid was very low and dirty when I got the truck, so i changed filter and drained the pan.. added 3.5 or so quarts of mercon/dex III. ATF... with plans to drain again very soon. As its dark red already. I just checked the owners book, it says Mercon V... but after checking my dipstick, it says Mercon on it.....

What do I need to be putting in this thing?

 

Mercon 5 is fine for this transmission. It's backwards compatible as far as I know.

 

Yes +1 ^^^

The new Mercon V is what you want now.

Fluids are always getting better, so what it came with is not always best or even available any more, i.e. whats printed on the dipstick or in the Owners manual is 1996 info, so 22 years out of date


Synthetics are also an option now.

 

Woukd I be safer using mercon v? Or could I use Valvoline Max life synthetic? It says mercon lv

 

Do not use mercon LV. It is not compatible with standard mercon / mercon V. Use something that specifically states mercon V. I recommend motorcraft fluid.

 

A few years ago, Ford discontinued Mercon and superseded to Mercon V.

Ford service bulletin: TSB 06-14-4