Is it a good idea to move from Synthetic oil to normal oil ?

[Ranger SVO]

Originally Posted by bronsin

Ive noticed people posting from places like the Middle East that they use 20W-50. Why I don't know. MAybe Toyota does?

Phoenix gets to 120 in the summer. Stop and go driving with the AC on under those conditions would be about the most extreme operating conditions I could imagine. I definitely would want some input from people with professional experience about what oil to use.

I have serious doubts 5W-30 is going to cut it.

And that's what I thought, but I was wrong. I go to Phoenix every summer to visit my mother-in-law. I usually spend a couple of weeks there then I go to Las Vegas for a week (I'm a teacher, so I'm off all summer).

I take either my 2010 Yaris or my 2012 Honda Civic.

I was concerned because Honda only recommends a 0W20 oil for the Civic. So I E-Mailed Mobil 1 back in 2013 about my concern, their response;

Dear Bill,

Thank you for your inquiry. Mobil 1 0W20 AFE does provide excellent high temperature protection and thermal stability is outstanding. It is certainly fine to use Mobil 1 0W20 in the environment that you described. According to the specifications for your vehicle, 0W20 is recommended and we highly recommend that you stay with your manufacturer's requirement.
Sincerely,
Mobil Help Desk
1-800-ASK-MOBIL

Well, if Mobil 1 0W20 AFE (what I use in the Honda) can handle Phoenix and Las Vegas temperatures, can't I assume that Mobil 1 5W30 EP (what I use in the Yaris) can also handle those extremes.