I just helped a friend change the oil in his 2003 Toyota 4Runner equipped with the 1GR-FE 4.0L V6 engine and we took pictures of the process. It should be the same procedure for all 2003 to 2009 4Runner vehicles with the 4 liter.
The manual and oil filler cap recommend using 5W-30 but he's been using Mobil 1 10W-30 since he bought the truck to better match the tropical South Florida climate.
Here's my guide page -
Cheers, Paul Michaels Ft. Lauderdale, FL