Any reason not to use 5w-30 year round?

[Axle]

I have a 2020 Mack MP8. Since 10w-30 is pretty common now I'm wondering if anyone can come up with a reason not to use 5w-30 year round. I live and operate in the upper Midwest where it can be necessary to need the 5w. The temperature range published by Mack says that oil can be used for the full range shown. I can find oil meeting the Mack engine oil spec from a few manufacturers. I'm not opposed to 10w in the summer, but some of the 5w-30 oils I've found seem to be slightly thicker at operating temp than the 10w-30 by the same manufacturer.

 

[fantastic]

There is no difference save for the slight improvement in starting during cold. 5w-30 is an all year oil & if you want to make sure you can find a 5w-30 in synthetic probably easier than a 10w-30.

Just noticed were talking about an HDEO. I would absolutely find one that meets CK-4 or spec which could be tricky. 5w-30 HDEO is not very common so on that front I'd keep it simple by using the spec'd 10w-30. Unless again, you can find a 5w-30 that meets spec.

 

[brandon9715]

Amsoil SS Diesel 5w30 (DHD) would be excellent.

 

[factorytuned2012]

run it

Mobil Delvac 1™ ESP 5W-30 | Mobil Delvac™ Engine Oils

Discover how Mobil Delvac1™ ESP 5W-30 and 5W-40 advanced full synthetic diesel engine oils deliver extended drain capability, fuel economy potential and exceptional low-temperature performance.

www.mobil.com

 

[Axle]

run it

Mobil Delvac 1™ ESP 5W-30 | Mobil Delvac™ Engine Oils

Discover how Mobil Delvac1™ ESP 5W-30 and 5W-40 advanced full synthetic diesel engine oils deliver extended drain capability, fuel economy potential and exceptional low-temperature performance.

www.mobil.com

That was an oil I'd been considering. I wonder if it would be suitable for extended intervals.

 

[brandon9715]

That was an oil I'd been considering. I wonder if it would be suitable for extended intervals.

It likely is, do a few UOAs and see.

 

[Kestas]

5W-30 buys you 15°F more cold when compared with 10w-30. Not a huge difference when you consider the large temperature swings we see in our climate.

 

[Axle]

5W-30 buys you 15°F more cold when compared with 10w-30. Not a huge difference when you consider the large temperature swings we see in our climate.

In the past I used 5w-40 with a cat c-12 and when the temp was -16°f it still cranked like it was 70°f outside, I'm hoping for similar cold weather performance.

And I think a few uoa's are certainly warranted. I'm curious to see how far I can push it without adding any bypass filtration. Factory recommended oci with fuel economy above 6mpg is 55,000 miles using non-Mack branded oil.

 

[BISCUT]

I've used 5-30 almost exclusively for a few decades. I was nervous once in Crawford Notch, NH in an 89 S-10 Blazer at temps nearing -30F. She was slow like molasses but she turned over. Hard to beat a 5-30 for general auto use in most of the US.

 

[factorytuned2012]

That was an oil I'd been considering. I wonder if it would be suitable for extended intervals.

States is capable of extended drains

 

[factorytuned2012]

That was an oil I'd been considering. I wonder if it would be suitable for extended intervals.

States is capable of extended drains

 

[Mainia]

I have a 2020 Mack MP8. Since 10w-30 is pretty common now I'm wondering if anyone can come up with a reason not to use 5w-30 year round. I live and operate in the upper Midwest where it can be necessary to need the 5w. The temperature range published by Mack says that oil can be used for the full range shown. I can find oil meeting the Mack engine oil spec from a few manufacturers. I'm not opposed to 10w in the summer, but some of the 5w-30 oils I've found seem to be slightly thicker at operating temp than the 10w-30 by the same manufacturer.

I do, and I am in Minnesota. I try to watch pour point and I semi warm my car up even in summer. I almost never start driving until my water temp is at 100 F in winter and 120F-ish in summer. I try to always try to expand my pistons before driving off.