Originally Posted By: 360kid
It should have Mercon V in it which is synthetic. He will only need to change that at the regular service interval, which may not be until 100,000 miles. I guess he could change it earlier if this boat haul is really that severe.
In my 2002 F150, with the tranny in mine, the manual doesn't even recommend changing the tranny fluid unless your truck falls under the severe service category. If it does fall under the severe use, then it still only recommends changing at 100,000 miles. However, some of the optional trannys for the 2002 F150, recommend changing the fluid every 30,000 miles. So, I would recommend he once again consult his owner's manual.
Oh how many answers one can find if they would only read the darn manual.
Mercon V can be met with a synthetic blend oil. The factory fill probably is that way.
Replace the ATF with a synthetic that is Mercon V approved, don't leave the factory fill in for more than 50K miles.
Factory oil change intervals are fine for regular or syn blend 5w20 oil, however, if the owner wants to extend the OCI, use synthetic 5w20 or synthetic 0w20