What Grade oil too run in winter?

[Fireman40]

I am from Maryland. It doesnt get all that cold here in MD but occasionally we get down in the 20's. Every now and then I get the ROMP. I have heard to lower my oil viscosity. I currently run the recomended 15w40. What grade can I go down to for winter but still have good protection in 40 or 50 degree weather.

[forddieseldoctor]

Look in your owner's manual in the 7.3 supplement book. There is a viscosity chart in there that will tell you what temps the different weights of oil are good for. I believe that 10w-30 is good for up to 80 or 90 degrees.

[tylerwitt34]

5-40 Rotella T Syth... IS what i run in mn and got over 60k on the truck with it with no probelms.

[Shooter04]

forddieseldoctor, your avatar pic is awesome.

To the OP, don't think this will help much seeing as how I'm from south Texas, but I run Motorcraft 15w40 year round. Last winter it got down in the 20's and my truck started. Didn't want to start.....but started....

[zpd307]

Originally Posted by Shooter04

Last winter it got down in the 20's and my truck started. Didn't want to start.....but started....

wow, 20's is like a heat wave up here during the winter..... ours have to start w/o a block heater in the -20's. dont always have a plug in handy. i started my 03 6.0 w/o a block heater when it was -34, actual air temp. wind chill was much worse. now that is what i would call barely wanting to start.... but i change to 5-40 synthetic rotella in the winter, every little bit helps.

[Shooter04]

Originally Posted by zpd307

wow, 20's is like a heat wave up here during the winter..... ours have to start w/o a block heater in the -20's. dont always have a plug in handy. i started my 03 6.0 w/o a block heater when it was -34, actual air temp. wind chill was much worse. now that is what i would call barely wanting to start.... but i change to 5-40 synthetic rotella in the winter, every little bit helps.

That sounds horrible lol. Last year was my first time seeing snow....it was awesome!! But yah most winters it's shorts and sandals no problem. I remember one Christmas it was like 75. I love Texas

But last winter was crazy. Up in Arlington, TX where i go for Christmas, it got down to 20 Christmas eve, and the city was basically shut down. Weren't enough salt trucks to cover all the roads so we were ordered to stay at home

[forddieseldoctor]

Originally Posted by Shooter04

forddieseldoctor, your avatar pic is awesome.

Thanks I found that in an e-mail.

[Stroken7.3]

Here in northern Utah it will go below 0 overnight in the coldest part of the winter. Me and all my friends and family with 7.3s run 15w40 Valvoline blue all year long, no problems.

[zpd307]

Originally Posted by duckslayer74

Here in northern Utah it will go below 0 overnight in the coldest part of the winter. Me and all my friends and family with 7.3s run 15w40 Valvoline blue all year long, no problems.

hey, me and a buddy are heading to tabiona to do some elk and muley hunting next week, leaving tuesday! mapquest only says 19.25 hours drive...

[Zaairman]

I run Rotella 5w40 Synthetic year round. Winter start ups got soooo much easier after I switched to it from 15w40.