They do not put in a recommended change interval as it will be greatly different from driver to driver. Some might benefit from a transaxle drain and refill every 30K miles, some might go quite a bit longer. With the clutch packs they have now - hard to just go by \"color\". Odor is a good indicator, but subject to interpretation.
Personally, I\'d stick with a shorter drain interval on the transaxle - no more than 30K miles on the Toyota Type T-IV ATF. I follow up with a pan drop every other drain and refill. Filter screen changed depending on what I find in the bottom of the pan.
2002 Corolla S, Silverstream, 1.8L 1ZZ-FE (VVT-i)
2003 Matrix XRS, Cosmic Blue, 1.8L 2ZZ-GE (VVTL-i) - RIP
2009 Matrix XRS, Blue Streak, 2.4L 2AZ-FE (VVT-i)