I have a 2003 Ford Expedition, with a 4.6L. can I use mercon V? also a 2004 F-350 superduty with a 6.0L diesel.will it also work in that transmission?

or what is recommended to use now?

Thanks

 

Step 1: Read owner's manual or transmission dipstick.
Step 2: If they say "MERCON", switch to "MERCON V".

 

It will say MERCON V for your truck. Use that.

DO NOT use MERCON LV, which many people think replaces MERCON V. It does NOT. MERCON LV will destroy the trans in your 2003.

The 2004 diesel requires MERCON SP or MERCON LV. MERCON V will destroy that transmission.

Funny how that works, but that's been my experience where I helped develop these transmissions.

 

If you don't have a owners manual, open the "Tech Info" thread atop the forum index page & scroll down to find the no cost Owner Manual down load link.

As Mark suggested above, use fluids that say in writing that they are licensed to meet or exceed the Specified Ford fluid requirements for your transmission.