is 5W30 ok for hot places? during daytime 107*F
or is it better to use 10W40?

 

I live in Southern Arizona, a pretty hot place in the summer I use 10W30 in my F and in my truck due to the summer heat and the mild winter. It's been working well for me. IMO, the 40 would be a bit to thick for general use.

Lou

 

The car was designed to run on 5W-30, why are you seeking oil for a hot climate? (I see you are in NY)

 

I live in philippines...i just grew up in NY

 

5W30 is fine. Remember the factory oil in there now has to work in all the temperature ranges including cold hence one reason why its 0W-20

 

Why don't you just add / Philippines next to New York so people know where you live? It might be pertinent when discussing something of this nature?

 

Monitor your oil temps, if they get higher than you are comfortable with, look into adding an additional oil to air cooler/heat exchanger.

 

OP, did you originally purchase your F in the Philippines? If yes, what grade does your owner's manual recommend? What do the local Lexus dealers recommend?

I spent a July & August in your beautiful country. From what I recall, it wasn't so much the heat as the humidity.

 

My car was imported from U.S.,its an 08 USDM,our lexus dealer here sold the isFs twice the price when imported...the temp during summer could go up to 100-107*F (daytime) yes its very humid here also...the local shop where i go to always recommends 10W40 for cars that normally use 5W30 because the head mechanic always says its very hot in our country,so a higher viscosity oil can take a little more beating (hard driving during daytime)...im thinking of trying 5W30 on my next oil change,just want to hear first what you guys have to say....

 

Or, as an alternative, you could use a synthetic oil (if you're not already doing so).

I made the switch for additional peace of mind, even though it's not in the owner's manual.