The Ford Triton v10 6.8L engine has a 7 qt oil capacity.
The recommended type of motor oil is Motorcraft® SAE 5W-20 and Premium Synthetic Blend Motor Oil XO-5W20-QSP.
Recommended oil by country
US and Canada 5W-20
Mexico 5W-30
The v10 gets about 9 mpg and has had a few problems.
You should change the oil every 7k miles on odometer or 5k if towing.
How to change the oil:
Remove oil cap
Use 16mm wrench to remove oil drain plug
Fill engine with 6.5 quarts of fresh oil
Start engine
Test level with dip stick, add a little more if needed.
