I felt the 10 W–30 would be the oil of choice here in North TX in the 07 T4R since that was used in our 2002 Camry. When I saw the 5 W 20 I called the service manager and asked if that was the correct wt for this area and he said yes. I have not checked the manuals good but I can remember options due to areas on some other brands in the past.
My current challenge is the mileage that the oil has to be changed to stay in the warranty’s guidelines. The Mfg and Local Dealers show differences in recommended services. The 02 Camry every 5,000 mi, 2010 Highlander every 10,000 per Mfg and 5,000 per 2nd Dealer on both. Our recent purchased 07 T4R every 5,000 or 6 mo per Dealer. Since 03 I have averaged 3,000 mi per year and changed my oil yearly in my Explorer that I replaced with the T4R. My goal was 5,000 and one yr oil change vs two but @ 2,000 mi now I will possibly drive 4,000 mi. For peace of mind and warranty purposes, I guess I need to change every 6 mo. With today’s oil standards and gas prices this would seem to be a waste if I only need to drive 3-5,000 mi. jow