Can I use Mobil 1 synthetic 5W-30 for hot weather in my XC70 2007

[Rattnalle]

In my part of the USA it can be over 90 F (33 C) after midnight.
Volvo does not suggest 5w30 for our climate for my year.
Also note many car manufacturers spec oil for best MPG when a slightly heavier oil might be better for engine protection

As I said the European recommendations differ. Sure it's a fuel economy thing and personally I use and would use 5w40 anyway since it's cheap and covers every condition. But the recommendation is there over here and the engines still easily do 300-400' km or more. If they wear out it's the stupid long life service interval of 30000 km rather than what oil is used.

[amblerman]

Mobil does make a 10w-40 HM variant in their Mobil 1 line if you reall want a HM variant.

Since your concern is hot weather, the 10 in. The front of the 10w-40 won’t affect you at all.

https://mobiloil.com/en/motor-oils/mobi ... gh-mileage

If you scroll down you can see all the viscosities it comes in.

-A

[June]

For what it's worth my dealer down here in Florida used 10W30 in my car during the hot months. Always full synthetic. My car had no trouble whatsoever switching back and forth every year from 5W30 to 10W30. So I think I would do the same with Mobil 1. Volvo tests these things relentlessly and gives the 86° cutoff, I'd follow their recommendations.

Since I started using Redline 100% synthetic oil I have been using 5W30 year round. That's been from 146K to the current 180K. The Redline oil has a high resistance to heat degradation. June

[Georgeandkira]

21 months after the original post.

I wonder what did mdv did?

[RickHaleParker]

It seems to indicate that 5W-30 oil is not good enough above 86°F. However, the oil is actually heated inside the engine by the engine heat way past 86°F. More close to 210°F or so.

The oil operating temperature is around 210°F. Your engine runs hotter at higher ambient temperatures.
The 5W-30 with go outside the oil operating range at a ambient temperature of 86°F or higher.
Most oils have a operating band with a spread of ~ 30°F.

[youtube][/youtube]

[abscate]

The ambient temp load is a small effect compared to the required load and heat generated by the engine.

If I had 5W-30 oil in and the temp reached 95F, I would back off 10 mph and reduce the heat in the engine by roughly (60/70)^2 or about 27% - that would keep that oil well in range, traffic permitting.