What Oil Are You Running in Serious Cold?
 

I'm talking in the -40 range because it's fairly common here. Diagram in the owners manual only goes to -20F/-30C. I've run 0W20 the entire time as recommended but I feel like this is an exception.

Before there's an potential confusion, -40 is the same in C and F.

Seeing as you can't go lower that 0W and AFAIK and can find multi grade oils are tested to -40 degrees. Why is this even a thread?
Serious question.

Like I'm sure many people on here, I've had 0w-20 in my car and driven it at -20f without issue multiple times.

Where do you live that -40 is "common"?
Are you using windchill temperatures? Windchill does not impact your oil viscosity so just use the actual temperature.
The 0W20 is fine for the temperatures anyplace in populated Canada. In fact we used 0W20 in the military vehicles in Alert where the temperatures are pushing -50 most of the winter. Mind you at that extreme hardly anything else worked properly anyway so oil was the least of the problems.

For the few very cold days to assist in a fast warm-up have you considered a block heater?

https://www.subarupartspros.com/part...ck-heater.html

I used to option my new cars with a block heater but have not needed to in the past 20 years. Reasoning when I will really need it there would be nothing to plug it in(winter camping anyone?) A good strong battery is more important when it gets that cold.

Some oils have shown to flow better at colder temperatures. Pennzoil Ultra platinum and amsoil signature are two I'm aware of that Excell in -40.

Project farm on YouTube did an oil analysis on a bunch of different brands and those two came out on top.

There are frequently one-to-two week periods south of Calgary that get well in to the deep -30 range without windchill. There are stretches where I’ll be cold starting it without a block heater, though it’ll work most of the winter. I just use the Toyota stuff so wondered if there was any better oil. It seems to be answered later on down the thread so it’s all sorted.

Thank you. Apparently, based on the responses, I didn’t word the initial post properly because this is the exact answer I’m looking for.

Car already has a block heater. Won't be able to use it sometimes (nowhere to plug in at work). I've run cars at that temp before without a block heater but they're either bigger trucks with monstrous batteries or small Honda's that would literally start at 0 Kelvin.

Was following the owners manual. If range only went down to -20, I was wondering if there was some other factor affecting the car's ability to run below that, potentially beyond just oil viscosity. No worries.

You could try a 0w16 or 0w8 for those stints. You’d see very slightly better cold flow due to less polymer doping to make the viscosity index spread with minimal engine wear increase, if at all. But, as others have said 0w20 should suffice, especially after 1600km or so when it’s sheared from fuel dilution and mechanical shearing when it’s probably closer to 0w16 anyway.

If it were me, I would use 0w-uHaul to move my butt someplace warmer. [emoji6]

Sent from my SM-G950U using Tapatalk

Give it a few months and I may be moving somewhere colder haha

i'm sure he'd be ok with you donating the first $1,000 to his gofundme.