STONEGREEN

I have a F-150XL with a 4.6 V-8 and an overdrive transmission. The truck has 34.5K miles. I purchased a little over a year ago with 23K miles on it We pull a pop-up camper weighing 1764 lbs and usually shlep along a few hundred lbs of gear when we go camping. The maintenance schedule says to do transmission fluid exchange at 60K miles. Since average mileage in a year is say 12-15K that would equate to 72K+ miles on a 6 year old vehicle. Does the age of the truck come into play here or is it strictly based on mileage when it comes to transmission maintenance? We are planning a trip from NW Ohio to Upper Maine next year pulling the camper and putting on about 2300 towing miles. This includes a lot of mountain driving on interstates. Should I be thinking about trans maintenance before we go and should I use synthetic fluid?

Any tips would be greatly appreciated.

TIA

STONEGREEN