Hi guys, I have a hemi gasser, but my question is about my Ford f350 diesel. my question isnt so much about the difference in motors. My question is that Im working in Tahoe right now with the temps reaching around 8 degrees at night. Im having a really hard time starting it in the morning and have been told that it is the Oil that I am using. So my question to you diesel heads is this. In the cold states, what kind of oil do you use in the winter? thank you for your time

 

oil doesnt have much effect on it unless your batteries cant turn it over because the oil is really thick (thats why with most diesels you want two high cold cranking amp batteries). if it has a block heater which it should being in tahoe, use it. the fuel/air mixture has to have some heat to it to get the explosion. could be bad glow plugs but i've seen several fords that just hate starting when its cold. plug in the block heater and let the glow plugs cycle is about all you can do for it.

 

*the block heater gets the water in the block warm which in turn heats the oil slightly warmer than the outside air temp, that will help if you're having problems cranking it over fast enough to make it fire. basically the colder it is the thicker the oil acts. figured i should post that as well it sort of helps with your oil question.

 

Use a 5w40 synthetic oil instead of 15w40 dino oil. It makes a BIG difference.

 

What year Ford? Their glow plugs are notorious for burning out. You can check them with an ohm meter. They are easy as spark plugs to replace. Well....some of them can suck to get access to.

 

I currently run 15-40 synthetic. Next year I will be running 5-40 in the winter.

However at only 9 degrees even with a 15-40 oil you really shouldn't be having that much issue starting. Definitely check the glow plugs.

 

I have a 5.9 cummins with 115,000 miles. I normally keep the truck garaged. Recently the temps dropped to 0 and I have treatment in fuel. I left the house made 1 stop and I reached normal temp. Left that stop and made one more where I stoped for 3 hours. I am sure the truck was cold. When I tried to start the key switch felt different. I let me block heater light go off and it was just dead. No click nothing. Batteries were original so first thought change batteries. I changed both and had the same effect. Also, tried to jump start with no luck. I am thinking the ignition switch is bad. Am I on the right track?

Thanks

 

thanks for the advice, no I dont have a block heater but am going to try the 5w40 sin today. This all started when I had the oil changed. thanks for ur help.....diesel rocks!

 

I run Rotella T 15W-40 in my 5.9 and its been below zero many mornings here and it fires right off.One morning it was 21 below and it started like it does when its 30 above.No block heater,just grid heater.