Engine oil in your Semi ?

[helmsdale]

I run 5w40 year round. Rebuilt the engine and broke it in on 5w40, so that's what itll stay on.

15w40 with a pan and block heater is sufficient, or a pan and diesel fired circulating heater will fire in any weather.

[LEP]

Have a C15 Cat that had 0w40 in it when I bought it, so I just continue with that. Year round.

The cummins has 15w40 in it year round. Outside but plugged in or a proheat on when its going to be used.

My brother has a C15 and a detroit. They run 15w40 year round.

[TASFarms]

0w40 if parked outside and 15w40 I’d parked in a shop. If your truck dies when it’s -30 it’s a lot easier to get it going if it has 0w40

[iceman]

If the Engine has a oil pan heater I don’t like to mix and match oil. 15w40 should be fine if plug in. Although running 0w40syn all year is probably only gonna hurt the wallet.

[farmaholic]

Hand pumping 15W40 from a barrel that is "cold" is no easy feat.

Pouring it is very slow too, so think about the flowability in the engine.

Although that is all we use.

Truck is outside but has an oil pan heater and block heater(non recirculating)

Gotta make sure it's plugged in for adequate time.

Good batteries aid in cold weather starting but don't thin highly viscous oil!!!!!