"Just because you can start at -30F (or even -40F) without plugging in, doesn't mean you should if you can help it."

My thoughts exactly, it's like people are so confident in this engine's ability to start in extreme cold temps (which it can with ease) that they don't ever plug it in, I don't get it. If I was worried about my electric bill being 30 bucks higher for 2 months out of the year, then I wouldn't have a 60,000 dollar truck.. The only time my truck isn't plugged in when it's frigid cold out is when I'm at work where I can't plug it in. If I'm at home and it's well below freezing, she gets plugged in, it makes me feel better anyway. I also like the benefit of not waiting for the truck to "warm up" when I am getting ready to leave for work. I just unplug and go. Saturday morning I started the truck when it was -13 degrees out (truck was plugged in at home) and it still took close to 40 minutes of driving just to reach the 190's on the oil temp. Took just over an hour for the trans to reach the 190's. I find myself watching the numerical temp screen like a hawk.

I see guys at work start their diesels slam it into gear before the engine has practically even fired on all cylinders. It is painful to watch. I usually let mine get to 70ish degrees oil/trans temp via high idle (1,400ish rpms) and then ill take off, which may be overkill but I plan to keep this truck for a VERY long time so I do it for personal relief. Does anybody else let their truck idle for a bit when it's very cold out?

 

When it was parked outside, my routine was remote start from inside the house, put shoes on, go outside, unplug, get ice scraper out, scrape frost/ice/snow off truck, by this time passengers would be in the truck, I'd get in, put seatbelt on and go... This was usually a 5 minute idle. I didn't always check it, but IIRC oil temp was at least +70F by then. I also actually wait for the "wait to start light" (or coil) to go out before I start. It's funny, but I hesitate to start a gas motor by habit.

In my 2011 6.7 which I primarily had in Miami, I never saw that light... But even in my heated garage up here, it takes a couple of seconds for it to go out.

FWIW, driving around up here in the sub zero temps, I've had all gauges go back towards 'C', instead of continuing to stay in the middle of the guage. What I find gets the coldest is the tranny temp and a cold tranny makes fuel mileage suffer. I almost want to put a tranny oil pan heater on and make it so I can keep it on while driving., almost.

 

Even with my gas rigs,I have never been a fire and go guy,even in the summer. I also always let them have a "cool down" for a minute after parking. It used to make me cringe to see guys leave the mill ( papermill) after their trucks have been sitting in the cold for 12 hrs....start em up and run down the road at the speed limit. They don't realize the wear and tear on the engine,trans,and the differentials....wheel bearings....jeesh.

 

Lots of mythology here. Don't mean to drag this thread sideways, but I've yet to see anything indicating additional wear by driving off easily immediately after the engine starts. I've run a half-dozen used oil analyses over the years, and they've all shown below normal for wear metals, and my vehicles NEVER idle. My current truck is no exception...-10*F and no frost on the windshield, it gets put in gear about three seconds after the engine fires.

Here's my latest UOA: https://www.ford-trucks.com/forums/1...l#post16795559

Seriously...with full oil pressure to the heads within seconds of the engine starting, exactly what is going to wear faster? By letting the truck idle to warm up, you are extending the amount of time that the engine runs below optimal temperature. My truck isn't a diesel, but what exactly would be different with one? I treated my 6.7L the same way.

 

Its a good discussion, I wouldn't worry about sending the thread sideways. I agree,letting a engine idle for too long isn't good either...to me I guess I worry about...the shock factor. Todays engines and engine oils are far better than even 10 yrs ago. We've had cold weather here for days at a time before,where automatic transmissions had a hard time shifting until they got warmed up some.

 

Hey, whatever creams your twinkie man. I just won't do that to my vehicles. Something about throwing it in gear when the engine is idling high just doesn't jive with me. I don't let my vehicles idle all that long, 70 degrees doesn't take long to get to with high idle. I can agree that too much idling is bad as well. Which is why I don't do it, but I do have the patience to wait 5 minutes to let the engine and trans fluids warm a bit. No mythology, lots of parts can be affected by rapid temp change like gaskets, etc. You just gotta do what feels right to you!

 

I generally agree...I don't just fire up and take off unless an emergency. When it's cold out, the biggest concern is that cold oil is pretty viscous and might not be flowing well to all areas of the engine. Oil pressure sensor is right at the filter. The oil jets in the head near the valves might not be absorbed on to the rocker shafts well.

That said, all modern engines are commanded to reduce idle the moment you take the transmission out of Park or Neutral.

 

I'm with you on everything except, When I fire the puppy up I drive off. My thinking is the faster I can warm the engine up, the better.
Also the heater works a lot sooner with the heater plugged in all night.

 

That's exactly my thinking. Modern engines are designed to spend their lives in a narrow operating temperature range, and the faster they get there, the better they function. If the internally lubricated parts didn't receive proper lubrication in seconds, an engine's lifespan would be measured in days instead of years.

Don't have a diesel truck anymore, but every oil analysis I've ever run has shown less than average wear metals. If driving off within seconds was doing any harm this wouldn't be the case.

 

It's also dependant on how you drive when you put it in gear. If you drive it nice and easy after initial start up, I'm sure all is fine for the most part. Likely not much different than setting high idle to 1500 for example. But a lot of things have to be taken into consideration here. For instance, when I leave the lot at work, I turn onto a 35 mph road for about 30 seconds before getting onto an 70 mph highway. This is one of the reasons I feel the need to let it warm a bit before I have to merge. It's one of those highways that you'll get ran over of you don't get up to full speed by the time you merge (Mad Max). I'm not about to gun it to merge on a highway when my temps are buried to C. When I lived in my previous place, I drove on 35 mph roads to non-busy 55 mph back roads with nothing but time to take it easy so I didn't warm it as much then.

 

Tom - Not knocking what works for you. However, I have some comments. Are you aware that the diesel trucks actually have a countdown timer if it's too cold to drive it immediately? So obviously at some point things need to be heated up enough to safely move. The tuck won't even let you shift out of park. It might not get cold enough where you are to trigger it. I've never seen more than a 10 second delay, some other brands (*cough* Dodge) have seen 60 second timers pop up here. Just by neighborhood design, I take it easy for the first 1/2 mile as the speed limit is only 25 mph and with speed bumps.

I never purposely wait longer than few minutes it took to get the truck cleaned off and me seat belted in. Remote start, get the defrosters, seat heaters, rapid supplemental heater, and coolant temp up so it is that much quicker for me to get comfortable. and yes, it doesn't truly get comfortable until you start moving.

I'm glad your UOA for your gassers and previous diesel were awesome and it's good feedback to know that if I decided to just jump in an go and the truck lets me, I am not damaging anything. I still think it's easier on things (like pumps) if they are allowed to heat up a little first.

One other tidbit I found out the hard way. In the cold, you might have enough fuel flow to idle, but not enough to move forward. The truck recirculates heated fuel, so your fuel gets warmer and easier to pump through the filters. That minute of idle time could be the difference between driving and stalling. (yep, stalled mine out a few times and that was trying to just high idle a little in the driveway) IMHO, It has to be easier on the fuel system to have warmer and enough fuel. I am mostly talking about operating in extreme cold temps. No one here will convince me that fuel pumps on our 6.7s are not finicky and that is something a UOA won't show.

So far my fuel issues occur when the weather gets colder before the producers are putting out winter blend fuel (or I am able to get it).

 

Yup, I remember seeing that in the diesel supplement for my '11. Was surprised to never actually see the message, even at -10* without the block heater plugged in. Don't know if the newer models have the same calibration or not.

That's all very true since the HPFP isn't oil-lubricated. Don't know how HPFP lubrication is affected by temperature, and that's a tough thing to know unless you're a tribologist or fuel system engineer. At what temperatures did you experience stalling?

 

I saw the message and had stalling issues at around -20f. Coldest air temp I measured last year was only -24F. This winter so far I have only measured -14F, but with 5 more months of winter left I'll probably see colder Temps than that.

It should be noted that once I got the right blend of fuel in, I didn't have stalling issues. And of course i remembered to plug in after that. Adding extra PS Arctic additive probably helped too.

Now that I park inside and rarely park outside long enough to get things down to sub zero Temps I may not see that message again.

I'm no fluid dynamics engineer either. Maybe one will chime in.

 

The warm up issue is why I did the upfitter mod. I start mine, let it idle for 3 - 5 minutes then hit the switch and let her idle up (got the high idle set at 800 rpm) till she hits the first mark. Takes about 10 minutes and the heater and defroster have then taken the worst of the cold out of the truck and most of the frost off the windshield.

Helps also for jump starting other vehicles and add the load when my compressors load.