let me see, my 2001 Honda Accord was one of the first cars designed for the new 5w20 oil (along with some other Honda and Ford models) and that was 5 years ago. It is true that back then 5w20 oil was very hard to get, but now just about any oil company makes 5w20 oil. Probably switching to 5w20 oil is new this year for Toyota so maybe we need to give service guys some time to get used to it, but when I asked my dealer what oil they'll put in my new TCH, he said 5w20 synthetic without even blinking. I read some article about thinner oil and the writer claimed 5w20 will reach all parts of engine faster than 5w30 etc, but I doubt wrong oil would actually damage the engine or have any other negative impact overall, as long as it is changed on time. In other words I will be putting 5w20 or 0w20 synthetic in my car but wouldn't loose my sleep if they did put regualr 5w30. Of course I intend to change the oil myself in the future (except for the first oil change done by the dealer) so i will know exactly what oil is there.