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I have always let all my trucks warm up for a bit. I don’t like to run a cold engine cause you could end up breaking something. Just my 2 cents
 

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At -17 (0F) I'll remote start and let my truck idle for the full 10 minutes. When I get in, the engine temperature gauge is still pinned COLD but at least my seat is warm. After driving for 10 minutes at 80kmh the gauge is half way to normal unless I have my 5er hooked up in which case the gauge reads normal in less than 2 minutes. I use the raw egg technique on the go pedal when cold - always the least amount of throttle to get to the speed I need.
 

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If it makes you feel any better my trucks been remote started for the last 15 minutes so i can be warm on my way to lunch.
Yeah but sitting on that seat, as hard as a wooden bench when it is REALLY cold is still not pleasant, like in Fairbanks (Ft Wainwright) in the Winter and Spring! :surprise:
 

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Blah... I just start it and go. By the time I’m out of the driveway it’s good to go....

But then again it’s 70 degrees here. Lol.

Couldn’t resist.
 

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Yeah but sitting on that seat, as hard as a wooden bench when it is REALLY cold is still not pleasant, like in Fairbanks (Ft Wainwright) in the Winter and Spring! :surprise:
Living in Fairbanks would be a justification to run your truck 24 hours a day all winter long in my book >:)
 

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Living in Fairbanks would be a justification to run your truck 24 hours a day all winter long in my book >:)
At the time I had a 79 Ford Bronco. Even gassers can get to be a pain to start in those temps.
 

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Living in Fairbanks would be a justification to run your truck 24 hours a day all winter long in my book >:)
I live in Delta Junction, about 100 miles from Fairbanks, but usually even colder here lol. I’ve been tempted to idle mine a lot more than I do.
 

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I let mine run for about a minute then drive it away but with my banks exhaust brake the exhaust brake stays on until 135degrees then it disengages it. The motor heats up quicker due to the exhaust restriction, pulling my 5th wheel I will warm the truck up 2-4 minutes. I also do not run my truck in the winter due to the corrosive salt they use on the roads around so from November 30 to April- June depending on the year I put it back on the road, one of these days I plan on moving to a warmer climate than Michigan then salt will no longer be an issue.
 

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So if I turn on my stock exhaust break would my truck heat up quicker? I usually let it idle for 5
Min in cold weather is that to long?
 

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So if I turn on my stock exhaust break would my truck heat up quicker? I usually let it idle for 5
Min in cold weather is that to long?
idling for 5, 10, 15 minutes is not going to hurt your truck any more then sitting in traffic for that same time. The idling thing is really blown out of proportion. The guys seeing negative results from idling are the the guys that idle them on job sites for hours, not minutes.

As for the exhaust brake, i don't think its going to do anything for you at idle, so i don't see it increasing engine load. If you have an LML, it should be getting close to operating temp after 5-10 minutes of idling. If you have an older truck, might be worth investing in a high idle if you want to warm up faster. my LB7 took 10-15 minutes to reach the same temp my LML does in 5 minutes with the high idle on. The higher idle may also produce less carbon buildup since the engines is running at a speed and temp less likely to incompletely burn the fuel.
 

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Duramax Dan
The high idle is RPO UF3 like redwngr stated. It has only one speed--1000 rpm on trucks. The upspeed on PTO trucks( almost all WT's/ cab and chassis) is 3 different speeds: 900/1200/1900. Last 2 3500's and current 4500 have had this system. If you want to verify the info look at tech bulletin 120F on upfitters site.

By the way, the high idle speed UF3 on anything other than a van is 1000 rpm not 1200. That is the speed for vans.

Guess we have beat this thread to death-- at least until next cold season and new owners didn't get an owners manual.

By the way redwngr, can you edit your post to include the PTO speed info and sticky note it for future use? People seem to confuse elevated idle with high/fast idle
Sambor,
on my 2017 the HIGH idle will bring the RPM to 1200 and will stay there as long as I leave it alone - sometimes all day. it is 1200 RPM for both trucks and vans
 

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So if I turn on my stock exhaust break would my truck heat up quicker? I usually let it idle for 5
Min in cold weather is that to long?
I don't believe the engine brake will make a difference since it is not active at idle

I drove a dumptruck years ago that had a Detroit engine ...if I left the jake on when I started it in cold weather .. the jake would activate because the oil was to cold/ thick to open the valve to shut it down OMG what a noise it would make
 

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'Turning on' the exhaust brake switch only 'enables' it in the software. The switch doesn't command it to operate.


The exhaust brake only activates when the transmission torque converter is locked.
This can vary based on vehicle speed, gear, and load.
 

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If you are using high idle function(controlled by cruise buttons) then yes, it will stay at the high idle speed until you step on brake/accelerator, or turn off cruise system.
On the two trucks I had with the UF3 option- high idle speed was 1000. Both later trucks are PTO equipped with 3 different speeds
 

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I don't believe the engine brake will make a difference since it is not active at idle

I drove a dumptruck years ago that had a Detroit engine ...if I left the jake on when I started it in cold weather .. the jake would activate because the oil was to cold/ thick to open the valve to shut it down OMG what a noise it would make
The pre heat feature is built into my Banks exhaust as according to Banks it remains engaged until my temperature reaches 135 degrees. Why do I believe that this works as stated is when I take off and the engine temperature gage is not registering yet the truck cruise control will not work until my coolant temperature registers on my gage. Also anytime the exhaust brake is engaged the cruise will not work until the brake is turned off. This setup comes with a pigtail that plugs into the coolant temperature switch which enables this feature. This exhaust brake was installed 3 years ago and is a Banks Exhaust brake for my LB7.
 

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The pre heat feature is built into my Banks exhaust as according to Banks it remains engaged until my temperature reaches 135 degrees. Why do I believe that this works as stated is when I take off and the engine temperature gage is not registering yet the truck cruise control will not work until my coolant temperature registers on my gage. Also anytime the exhaust brake is engaged the cruise will not work until the brake is turned off. This setup comes with a pigtail that plugs into the coolant temperature switch which enables this feature. This exhaust brake was installed 3 years ago and is a Banks Exhaust brake for my LB7.
Sounds like the aftermarket exhaust brake on your LB7 does not function the same as the factory exhaust brake.

The exhaust brake on LML and L5P will work when the cruise is engaged.

'Elevated Idle' function is basically a factory 'pre-heat function'.
 

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The exhaust brake on LML and L5P....
Turbo Brake, not exhaust.
LB7 turbo....no TB possible.
 

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Turbo Brake, not exhaust.
LB7 turbo....no TB possible.
Whatever...

The point was that on the variable vane system the cruise and brake can be active at the same time -- unlike the banks system on his LB7.

Gives the factory system the ability to work to maintain cruise set point on long downgrades, which the Banks system apparently cannot do.
 

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Whatever...

The point was that on the variable vane system the cruise and brake can be active at the same time -- unlike the banks system on his LB7.

Gives the factory system the ability to work to maintain cruise set point on long downgrades, which the Banks system apparently cannot do.
The point to my thread was that the Banks system is engaged until the temperature goes to 135 degrees and that this feature warms my Duramax up a little quicker.
 

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The pre heat feature is built into my Banks exhaust as according to Banks it remains engaged until my temperature reaches 135 degrees. Why do I believe that this works as stated is when I take off and the engine temperature gage is not registering yet the truck cruise control will not work until my coolant temperature registers on my gage. Also anytime the exhaust brake is engaged the cruise will not work until the brake is turned off. This setup comes with a pigtail that plugs into the coolant temperature switch which enables this feature. This exhaust brake was installed 3 years ago and is a Banks Exhaust brake for my LB7.
You are comparing apples to volvos here though. The LB7 has a fixed geometry turbo so you are actively closing a valve in the exhaust to create the back pressure. On the trucks in question there is no valve in the exhaust. The turbo vanes move to increase back pressure which results in braking force. Since the truck is idling though, even with the vanes all the way shut, there will not be a significant increase in back pressure worthy of warming the engine up noticeably faster. You cannot compare a factory system, to an aftermarket system that functions on completely different mechanical principals.

Enabling the turbo brake on a VGT truck will only tell the controller that it is allowed to engage the brake as it sees fit. With the switch off this feature is disables so the control module does not attempt to activate the brake regardless of the situation. This means that the brake will be enabled, but only active when the truck senses conditions that would require activation. Idling is not one of these conditions by default. That said. You can get tuning that will close the vanes for you at idle. Thats probably the closest you will get to the same function as what you have on your LB7 without installing a physical exhaust brake. This would be a "hiss tune" if i have my terminology correct. At high idle with this tune, you may see some benefit from it, but im 99% sure its just there so your truck sounds like a jet engine warming up.



Whatever...

The point was that on the variable vane system the cruise and brake can be active at the same time -- unlike the banks system on his LB7.

Gives the factory system the ability to work to maintain cruise set point on long downgrades, which the Banks system apparently cannot do.
Honestly.... would you trust an aftermarket system to on the fly close a butterfly valve in your exhaust as it sees fit to assist in grade braking? even if it wasnt a banks part id still be very skeptical of that device.
 
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