[Ricardo]

Took my RSX for maintenance and the boys used Motul 5100 15w40 semisynthetic oil. Will it be fine or better to switch to Mobil 1 0w40?

I´m in the tropics and it is nearly impossible to get the JD oil. Needless to say I am running it in a very humid and hot climate all year round. In fact every now and then it hits 38 degrees celsius, just a tad below 100 F.

 

[200mph]

Why are you concerned about the low temperature rating of the oil (0 or 15 in your case) when your ambient temps are so high?

in your case I would have no problem with the 15w-40 oil.

 

[Ronaldb]

I run 15-40 Rotella in all my vehicles never had a issue

 

[Ronaldb]

And im in Boulder co area

 

[Ricardo]

Thanks. Asking because JD suggests 0w40

 

[200mph]

If you research what the two numbers mean (0 and 40, or 15 and 40). You’ll see why there is little concern about the lower viscosity number given your “tropical” temperatures.