Adding supp heat?
Lead Driver
Joined: Nov 2005
Posts: 8,477
Likes: 4,971
I'm sure it could be added, probably have to disassemble the dash to do it, then would need to be added to the electronics with forscan or oem scan tool.
Wouldn't be cheap or easy.
Also, the factory option comes with the 397 amp dual alternators to make sure it has sufficient amps.
Wouldn't be cheap or easy.
Also, the factory option comes with the 397 amp dual alternators to make sure it has sufficient amps.
Posting Guru
Joined: Feb 2018
Posts: 1,555
Likes: 516
There is a thread here that covers how to do it. It's a very complex and fairly expensive job. It would be easier to execute a mission to the moon. The consensus is if it's not done when the truck was built, don't bother.
Posting Guru
Joined: Feb 2018
Posts: 1,555
Likes: 516
Maybe. I have nothing with which to compare my 2018 to. It may be a conflict with your expectations, or how you were using it. For clearing a frosty or icy windshield, it works pretty good. It can knock down that biting chill while you wait for seat heaters to come up to speed. And really, other than windshield defrosting, seat heaters are more effective and bring more comfort than the supp heater. That is why I got front and rear heated seats. I don't know why it is not standard for every diesel build other than the expense of the alternator upgrade. It's not like it adds a grand to the build.
FTE Community Team
Joined: Mar 2017
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From: Florida
im not kidding.
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Mountain Pass
Joined: Jan 2019
Posts: 205
Likes: 78
It makes a noticeable difference to me. It's not a high heat but if I remote start my truck and get in it say 5 minutes later it is definitely warmer. It also helps clear the windshield of frost which can take forever without it as these diesels take a long time to warm up especially at an idle. If you keep your truck in the garage you probably won't notice it since you wouldn't remote start your truck.
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Brett Foote
Fleet Mechanic
Joined: Sep 2013
Posts: 1,303
Likes: 84
not familiar with adding the supp heat. That said you could hookup the high idle circuit to one of your upfitters. Then you just have to remember to set the emergency brake when exiting the vehicle. Upfitters could be left on as it needs the E brake and park requirements met to go into high idle mode. It would help warm the engine a bit faster.
Lead Driver
Joined: May 2021
Posts: 5,872
Likes: 3,508
From: Uh oh, CA
I didn’t add it to mine. If I could go back I would have added it, but I didn’t know any better… I did add the engine block heater though. I have only been in temps as low as the mid to high 20’s so far but with the engine block heater plugged in for a few hours I haven’t had any concerns. The EOT starts higher/warmer than it would without the heater and seem to climb pretty fast once I start driving. I’m about 4 miles from work and drive through several red lights to get here, so no chance for running higher RPMs but the air coming from the vents are warm by the time I get here. I do have a high idle wired into one of my upfitter switches so I typically remote start the truck when I’m putting my boots on to walk out the door. I leave the high idle engaged so when it cranks the RPMs kick up to 1200, then I walk out and unplug the truck and roll the extension cord back up. So far my EOT has been around 70-80F by the time I get in the truck and get settled and pull out of the drive. Around 100F I can start feeling warm air pretty good and it doesn’t take long to get there. I just got a Banks IDash, so I’m curious to see what my ECT’s actually are too when using the engine block heater.
Adding the engine block heater is less expensive and easier than adding the supplemental heat aftermarket as far as I understand.
Adding the engine block heater is less expensive and easier than adding the supplemental heat aftermarket as far as I understand.
Lead Driver
Joined: Nov 2005
Posts: 8,477
Likes: 4,971
I have the supplemental cab heater and it works great, cold truck but extremely warm heater output.
It actually sometimes works too well, have to turn the temp selector way down.
And, for the cost, it was just a no-brainer to me, and you get the dual alternators.
It actually sometimes works too well, have to turn the temp selector way down.
And, for the cost, it was just a no-brainer to me, and you get the dual alternators.
Tuned
Joined: Sep 2019
Posts: 352
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Mountain Pass
Joined: Nov 2021
Posts: 109
Likes: 70
From: Virginia Beach
Daddy, unless you have the garage door open, or some serious ventilation, or a detached garage, that’s not something I would recommend as a safe practice. Just my two cents.
Joe
Joe