block heater
Lead Driver
Joined: Dec 2013
Posts: 9,762
Likes: 115
Kill-a-watt shows mine in the 900 watt range too.
And Rapid Supplemental Heater comes on around +25F, but there is more logic to it than that. There has to be a certain temp spread between inside temp and HVAC desired temp too.
For some reason I never noticed much of a difference for only a 3 hour plug in before leaving. An 8 hour before oil temps were in that 40-50F range stated if it was sub zero out. Despite that the block heater is for the truck and not you, the quicker the truck warms up, the quicker you do.
DocZenith did an awesome spreadsheet on just how well the Rapid Supplemental Heater works. I'd try to always get that option - unless I moved back to South Florida.
And Rapid Supplemental Heater comes on around +25F, but there is more logic to it than that. There has to be a certain temp spread between inside temp and HVAC desired temp too.
For some reason I never noticed much of a difference for only a 3 hour plug in before leaving. An 8 hour before oil temps were in that 40-50F range stated if it was sub zero out. Despite that the block heater is for the truck and not you, the quicker the truck warms up, the quicker you do.
DocZenith did an awesome spreadsheet on just how well the Rapid Supplemental Heater works. I'd try to always get that option - unless I moved back to South Florida.
Fleet Mechanic
Joined: Dec 2015
Posts: 1,521
Likes: 412
From: Washington Coast
I was always taught to plug em in as soon as you park for the night. It's always easier to maintain temperature then to raise it. Dad was a heavy tow truck driver in Michigan. We did that even down in Arkansas.
I know that they only put block heaters in trucks to be sold in the northern tier of states now days. My truck started out in Missouri so it didn't have it.
That's what we did on the trucks when I worked at U-haul in Washington State. Just makes them easier to start. Still cold in the cab.
I had a 6.9 and trying to start it at less than 30 F was next to impossible unless the block heater had been plugged in.
I know that they only put block heaters in trucks to be sold in the northern tier of states now days. My truck started out in Missouri so it didn't have it.
That's what we did on the trucks when I worked at U-haul in Washington State. Just makes them easier to start. Still cold in the cab.
I had a 6.9 and trying to start it at less than 30 F was next to impossible unless the block heater had been plugged in.
Senior User
Joined: Sep 2016
Posts: 146
Likes: 0
From: Skowhegan, Me.
That makes sense actually. I have been in Maine my whole 52 yrs and recall the diesels of old were always pugged in overnight. But I know of a bunch of guys that never plug their newer trucks in unless it gets below 0. It is 6pm here now and it is 1 above and I just plugged mine in for the night as I may have to head out early.
Super Moderator
Joined: Aug 2003
Posts: 25,479
Likes: 742
From: Isanti, MN
Lots of folks have started their trucks without issue at -30* without aid of a block heater. No reason in the world to leave the truck plugged in overnight unless parking on the dark side of the moon.
I read an interesting TSB for the F150s earlier this week about clogged heater cores being caused by overuse of the block heater. Don't understand the principle behind this, but the downside may be more than another $30 on your electric bill.
I read an interesting TSB for the F150s earlier this week about clogged heater cores being caused by overuse of the block heater. Don't understand the principle behind this, but the downside may be more than another $30 on your electric bill.
Senior User
Joined: Jan 2015
Posts: 310
Likes: 1
From: KC
Block Heater
I installed a Motorcraft block heater in my 09 V10 so that I could unplug it and leave for work without waiting 5 or so minutes. In that particular truck, the block heater would actually keep the coolant warm enough to register on the dummy gauge (cold/hot gauge). I recently started plugging my 2016 Powerstroke in when I got home from work since it's been around 15ish degrees lately and it has yet to be warm enough to register on the dummy gauge when I go to start it the next morning. Actually, the first time I plugged it in and then started it the next morning, I thought it wasn't working because I turned the power on and the temp gauge did not move. But I quickly realized it was working when I started the truck and cycled the info screen to read out the numerical oil and trans temps which reflected the warmer oil temp. Plus to me it's easy to tell just by the way the engine sounds and how high or low it idles. I, like many others, use a heavy gauge chord that is lit at the plug. I also leave the truck plugged in overnight on nights where the temp is in the teens without losing sleep over it. 
Lead Driver
Joined: Dec 2013
Posts: 9,762
Likes: 115
That makes sense actually. I have been in Maine my whole 52 yrs and recall the diesels of old were always pugged in overnight. But I know of a bunch of guys that never plug their newer trucks in unless it gets below 0. It is 6pm here now and it is 1 above and I just plugged mine in for the night as I may have to head out early.
Really glad our 6.7s are as good as they are.
Tom - That sucks. It's like you can't win for losing... I also read that CR is downgrading the reliability of the new F150 too. My only experience with them was a brand new rental - I was the first one to rent it - and it had al kinds of electrical gremlins.
Its Comin Right for us!
Joined: Feb 2005
Posts: 12,205
Likes: 2,661
From: GA
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Hotshot
Joined: Jul 2005
Posts: 13,834
Likes: 26
From: Middle Tn.
I was always taught to plug em in as soon as you park for the night. It's always easier to maintain temperature then to raise it. Dad was a heavy tow truck driver in Michigan. We did that even down in Arkansas.
I know that they only put block heaters in trucks to be sold in the northern tier of states now days. My truck started out in Missouri so it didn't have it.
That's what we did on the trucks when I worked at U-haul in Washington State. Just makes them easier to start. Still cold in the cab.
I had a 6.9 and trying to start it at less than 30 F was next to impossible unless the block heater had been plugged in.
I know that they only put block heaters in trucks to be sold in the northern tier of states now days. My truck started out in Missouri so it didn't have it.
That's what we did on the trucks when I worked at U-haul in Washington State. Just makes them easier to start. Still cold in the cab.
I had a 6.9 and trying to start it at less than 30 F was next to impossible unless the block heater had been plugged in.
Postmaster
Joined: Nov 2003
Posts: 3,595
Likes: 0
From: Utah County, UT
My 2016 it is in passenger side bumper behind front plate. On my 7.3 it was on the roar driver side well bundled up.
Hotshot
Joined: Apr 2013
Posts: 10,122
Likes: 657
From: NH
Its harder to find on the 17's but it's tucked up into a clip in the top of the bumper opening right above the passenger side tow hook.
Lead Driver
Joined: Dec 2013
Posts: 9,762
Likes: 115
It's standard in 14 states and optional in others. I had one on my Florida shipped to truck. Not like you can't get it, i just isn't standard. Invoice it's a $35 option. MSRP IIRC, was $75. A drop in the bucket on an at least $60k, if not $70k truck. (or in the case of a 2017, potentially an $80k truck)
One other thing is the rapid, supplemental heater is supposed to now be standard in those 14 states as well.
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My .02.
Just because you can start at -30F (or even -40F) without plugging in, doesn't mean you should if you can help it. There is a public service announcement here that you should plug in at +20F or lower even gassers. Granted the reason is emissions and not necessarily motor wear/tear. A couple of times a year, the city gives out free timers too.
One other thing is the rapid, supplemental heater is supposed to now be standard in those 14 states as well.
-
My .02.
Just because you can start at -30F (or even -40F) without plugging in, doesn't mean you should if you can help it. There is a public service announcement here that you should plug in at +20F or lower even gassers. Granted the reason is emissions and not necessarily motor wear/tear. A couple of times a year, the city gives out free timers too.