jagtoes

This is one of those 3rd rail arguments that continues to be a issue for some people. Whether you stick with the original 5W-30 dino oil or go to a syn doesn't really matter over the life of the engine provided you change it at some consistent interval. So if you don't mind changing the oil at 5K miles then do it and if you want to use syn oil then go ahead. I do agree that if you go from 5W-30 dino to 0W-20 syn you should never go back or mix the two. So if you want to go 10K then do so. These are not unique engines and are just a good run of the mill V6. I wouldn't get to excited about it . It's just like when Lexus recommended to use premium gas in the early days and then switched in the later cars. Do what you want but just do it.

LexBob2

I agree. At a minimum if you follow the manufacturers recommendations for service you should be fine. You can do more if you feel it's necessary. There are hundreds of thousands, if not over a million, of this 3.5 V6 in service and it's been VERY reliable. It's used in the ES, RX, Camry, Avalon, Venza, Rav4, Highlander and Sienna so there is a long track record with it.