I live in East Ky. and we can get down to zero F and sometimes a bit below during the worst months of December through February. I am going to use Mobil1 0w20 this year for those months only, dino Chevron the reat of the year.
I'm using Mobil1 now in Indiana. It gets reasonably cold here but nothing to write home about.
Looking back nostalgically, I lived in Northern Michigan 10 years ago, and used whatever 5W-30 came out of Jiffy Lube's tank. I don't recall having any problems with -5F starts with a cheap Chevy that was parked outside, other than the time I left an interior light on for 3 days and killed the battery. I remember my real concern being getting the thick layers of ice off the car. Come to think of it, I drove about 1 mile to work and back during those winters...that could NOT have been good.
I think I would use syn in the winter if I lived up there again, but it would probably be unecessary
It gets as low as -40C almost every year, with multi-week stretches below -30C, and the vast majority of people use 5W-30 dino. The high viscosity of the dino at these temps probably increases engine wear a little and makes for somewhat harder starts, but it seems to work for most. However, I believe the advantages of a synthetic are worth the minimal additional cost ($60 a year isn't much!), so I've been using 5W-30 M1 for a couple years with no problems, cold-starting or otherwise. I'm going to try a 0W-30 synthetic for the winter now that it's readily available. I expect it will save some fuel and make for even easier starts.
I live in northern Minnesota (moved here from northern Virginia in 87). I had a dino oil in the first winter here, after one morning of looking at thick syrup on the dip stick (-22F) and no start that sent me to researching oils (an addiction that I haven't been able to kick yet).
Have used Amsoil (89-94) then went with Mobil 1 (just so much easier to find and less expensive).
In 95 the actual temp was -54F one morning, but normally they are milder at -30 to -40 below zero f.
Never have had a problem starting since using synthetics (sometimes in the garage and sometimes car not in garage).
But a good thing to have on your car up here is the engine block heater; if one uses that even the dino's will be just fine.
I lived in New Hampshire for 10 years and we routinely got -15 to -20. Very occasionally we would see -30.
I used M1 10w30 in my Honda Civic that never spent a day of its life in the garage. I never had a starting problem in the mornings. When I got rid of the car with over 216,000 miles on it, the engine was still running strong and didn't burn any oil. I did mostly 3k oil changes though, until the last 50K miles or so when I increased to 5k - 6K intervals.
I live in Minnesota, in the Twin Cities. Temps here generally aren't as cold as northern MN, but are much colder than most of the US in the winter time. We also have a cabin on the edge of the Boundary Waters Canoe Area (BWCA) near the canadian border. I've had no issues using dino 5w30 all the way down to -30F without problems. Of course, nothing else is happy about the cold (tires frozen flat spots, all the other fluids (tranny, gears, etc). I also do not have a block heater on anything I own, though I probably should!
I lived in Colorado for five years, and yes, it occasionally got cold. Still wasn't the same as home though!
I'm sure my wear numbers would look better with a syn oil in the cold, but I haven't had any issues a better battery couldn't solve in cold weather!
Michigan, we average of 200 inches of snow yearly.
I have been using synthetic oil since 1977, started when Mobil 1 came out but switched to Amsoil soon after. I worked all over and often left my vehicle parked for a week, before the switch to synthetic, I was having problems with no start in cold weather (-30°F). Once I switched to synthetic in 1977, I have never to this day had a vehicle that did not start in the cold weather. I had a 1979 Chevy 3/4 ton custom van. In the cold weather, the trans was slow to move. When I put it in drive, it seemed to take 10 seconds or more to be able to drive away. I had a trans shop install synthetic (Amsoil) and the first cold morning I put it it drive and it was acted just like it was 50° out. I once pulled the dipstick on the trans and the factory ATF was like jello.
When you say you lived in Northern Michigan, you mean the northern LP? I have not seen any Jiffy Lubes north of the bridge in the real Northern Michigan (UP).
2002 Firebird Trans Am WS6
2001 GMC SLT Ext Cab Z71
1993 Chevy Lumina V6 Sedan
1992 Chevy Silverado SWB 4x4 (plow and bush truck)
I live in Edmonton Alberta. We have all the extremes living on the Prairies.
We have the cold temp's in the winter -30C(-22F)
and the +30C(86F) in the summer.
I run Amsoil Series 2000 Synthetic 0W-30 in the winter and Amsoil Series 2000 Synthetic 20W-50 in the summer( I pull a trailer).
Also have Ams in tranny and rearend.