Overthinking oil of course

[JCoastie]

I live in the south, temps reach freezing and not much below 32f only a single handful of times each year. I have no reason to use the tractor when it's that cold.
I have a 2020 LS MT240 which does have a turbo.
I just recently did the 50hr service and changed all filters and engine oil. I put dino 15w40 back in it.
My plan is to switch to synthetic at 100 hours.

The manual says 15w40 is fine down to 5f which we'll both never see and I'll never be out in (it's why we moved to the south)
In 10 years, I've seen the teens (f) maybe twice, and I saw them from inside the heated house. Upper 20s maybe 3 or 4 times per year, and 40/45+ by time I may hop on a tractor.
Summers see temps consistently up near 100f, I expect ~60hrs use per year.

The tractor stays outside under a carport.

Should I stick with 15w40, or use 5w40 just for extra protection for the turbo?

 

[Peter 315]

I run 15w40 and have a turbo.. I think 5w-40 or 15w-40 will be fine its up to you...

 

[MF243RedTop]

I'm next door to you somewhere..
I've always just used 15w40..
Just like you minimal use during the winter months.
When it is down that low, crank and let warm before hard use..
Never had any issues.

 

[Roadworthy]

I live in Washington state. I've never used anything but 15W-40. It's been a long time since I've seen it go below +15 degrees here.

 

[RjCorazza]

I'm sure 15w40 is adequate, and likely more available in your area. My tractor sees some snow duty in occasional single digit temps, so my preference is 5w40 synthetic, with the correct API rating.

 

[Tinhack]

15W-40 in use in South Texas too. None of my tractors have cabs. It can hit 110 in the shade here. Had an early winter--Hit 32 twice already! As OP says; when it's too cold or too hot (here), you'll find me inside.

 

[RalphVa]

Ran 5w30 in the VW TDI, turbo diesel injection, for nearly 7 years. Now running 5w30 in both the 2025R and Isuuzu generator driver. Get it from VW. Will try for M1 0w30 online in future. Better to get the oil instantly to the upper end on starts. On my VW Cabrio it had one hydraulic valve lifter that would drain down and then hammer until refilled on startup. 0w30 was the only thing that stopped the hammer, even in warm weather.

Ralph

 

[DEWFPO]

If you never run your engine in cold weather this discussion is a moot point. It doesn't matter what's in a sleeping crankcase.

DEWFPO

 

[RalphVa]

No. My experience with the hydraulic valve on the VW Cabrio begs to differ. Even 5w30 didn't completely stop the valve hammering. 0w30 did.

With 15w40 oil, you've probably a good 2 or 3 seconds even in warm weather that it takes for the oil pump to get suction and to pump the oil to the upper valve area. With a 0w40 or 0w30, it would be almost instantaneous.

Ralph

 

[Sberry]

If you changed at 50 why fuss with it again at 100, run it a while. There isnt magic pixie dust in any of it.