Oil viscosity in hot tropical climate

[ricardo-cr23]

Hello! I have a Yaris 2007 sedan 1.5L V4 US version with 190k miles on it. The manual recommends to use 5W-30, but the dealership in Costa Rica is telling me that I have to use 20w-50 due to hot tropical climate. I'm concerned about this because I have read that running ticker oil is bad for newer engines, specially the ones that have VVT-i.

What I am currently using is Valvoline High Mileage MaxLife 10W-30 Synthetic Blend. I change it every 5k miles.

A previous owner had this car and didn't know which oil was being used in it, so I'm pretty sure they were putting 20w-50 since it is the standard here, so I swapped it to 10W-30, and the only thing I noticed is that the oil consumption is a bit bigger, it burns like a quart and a bit between oil changes.

My car does not burn oil through the escape, and there are no oil leaks. Ths is how the engine sounds when it is cold: https://youtube.com/shorts/Qe3OQspBDKw?feature=share

[bronsin]

If the Toyota dealer is telling you to do that that’s what I would do. It’s kind of a difficult problem! If the temperature gets below 80° I would switch back to the 10W-30 or the 5W-30. But if it’s like 95° and 95% humidity I think the 20 W 50 would be better. If you have the 20 W 50 in there listen carefully to the engine when you start it. If it rattles a little I’d go to the 10W-30 or the 5W-30.

I sometimes mix 10W-40 and 5W-30 half-and-half in my wife’s Camry in the summer. When it’s 90° out the oil is really thin! The car is 19 years old this September and has over 200,000 miles on it.

[ricardo-cr23]

Right now is 12:00 p.m. and temp is 85º with 51 percent humidity. Rarely goes over that. See this link for historical climate where I live: https://weatherspark.com/y/15529/Average-Weather-in-Alajuela-Costa-Rica-Year-Round
When I changed to 10w-30 I noticed that cold starts were way better. So what do you think about changing to 10w-40? Cold viscosity is the same as what I have now, and it stays a bit ticker when hot.

I have another friend that recently changed from 20w-50 to 10w-30 and he also noticed that the cold start is way better.

EDIT: I do remember that when going on long trips, I notice that the motor starts to rattle a bit, could it be because of the heat?

[bronsin]

That doesn’t sound tropical at all. When you get off an airplane in a tropical country, after living in a temperate, the heat is unbelievable. You can’t BELIEVE you are going to have to get used to this.

I would stick with 10W-30.

[sh0rtlife]

stick with the maxlife your running, 20/50 is WAY too thick for these lil engines..id say if you were in the middle of africa or some other desert where its perminantly hot as hell then yeah 20/50 would be ok so long as you didnt drive at night.....as you have to consider both your hot and your cold driving thus the 10/30 hot/cold

[ricardo-cr23]

Hahaha yeah here's not that hot compared to other tropical countries. And thanks guys, appreciate the advice. I'll stick to what I'm using right now.

[rayfloyd170]

I am living and working in saudi arabia and used the cheapest full syn 5w30 since day 1. Now at ~228,000 KM and engine is still silent as ever. I drive it daily from home to my workplace, roundtrip at around ~250km ave speed 120-130kph at close to 4000rpm. This engine is a beauty. 5w30 baby is fine for your climate.