Viral Scoop
updates | May 14, 2026

How long can a Duramax idle?

How Long Can I Leave My Duramax Idling? Regardless of when you run your LB7 vehicle at idle, your safety equipment should do its job. It seems Chevy explains the lly trucks with an engine oil cooler and valve are only able to run for four minutes MAX.

How long can I leave my Duramax idling?

Any LB7 truck can be ran at idle with no problem. GM says the lly and up trucks with an egr cooler and valve can only be idled for 10 minutes MAX is what gm technical assistance tells us.

Does it hurt a Duramax to idle?

It won't hurt a thing.

Is it OK to idle a diesel engine for a long time?

Unnecessary idling wastes fuel, causes air pollution and increases engine wear. An idling diesel engine produces much higher emissions than it would while using the same amount of fuel under load. Extended idling causes a build-up of soot inside the engine and results in a puff of black smoke when the engine revs.

Can you idle up a Duramax?

Start the truck then press the set button on the cruise control making sure your foot is not on the brake. This will raise the idle to about 1200 rpm. Pressing the resume button on the cruise control will raise the idle to about 1800 rpm. You can switch between idle rpm by pressing the opposite button.

34 related questions found

How long should you let a Duramax warm up?

2-3 minutes is plenty unless it's extremely cold and you didn't plug in the block heater. You need just enough to get oil circulated and let the pistons warm up a little, no more than 10 minutes on a very cold day (-10 and colder).

How do I make my 2020 Duramax high idle?

High idle can be engaged by setting the park brake and hitting the cruise button but this will only work if the truck has the high idle switch installed - option UF3. With the high idle on it will idle at 1200rpm until you hit the brake, parking brake or cruise.

Can a diesel idle all night?

Even so, idling for extended periods of time is not good for your engine, even if you let your engine run overnight to keep warm. Diesel engines are durable, and semi drivers who let their engines run overnight can still expect hundreds of thousands of miles out of them.

Can I leave my diesel truck running while fueling?

Yes, technically you can. In short, if there is no spark nearby, it is safe to put gas into a fuel tank while a car is running. While you may not want to leave your car running, there is one solid reason not to: the fuel pumps have signs that direct you to turn off your vehicle while you are pumping.

What is a lot of hours on a diesel engine?

How Many Engine Hours Is Alot For A Diesel? The average diesel engine lasts between 6,000 and 8,000 hours while properly maintained, and requires much less work and money than gas engine replacements.

How much diesel does a Duramax use idling?

Registered. On a recent test, I determined that my LLY burns about . 58 GPH when high idling.

Can you pump diesel while running?

Registered. Your buddy is right, you can do it, and it is good to cool the turbo before shutting down.

Should you let your diesel engine warm up?

In order to start a diesel engine and keep it running in cold weather, you must make sure you allow plenty of time for your engine to warm up. If you do not let your engine warm up before driving, you will make it work harder than necessary, which will lead to problems later on.

How long can you let diesel sit?

Under ideal conditions, diesel fuel can be stored between six and twelve months. To extend the life past twelve months, even under the best conditions, it needs to be treated with fuel stabilizers and biocides.

Do I need to let my Turbo diesel cool down?

Since exhaust gases keep it hot, it's only logical that once you shut the engine off the turbo temperature can only cool down, unlike the cooling system on the engine. So in summary ALL engines with a cooling system need a cool down after long sustained full load. This means everyone towing or running fully loaded.

Why do truckers leave their trucks running all night?

Truckers, both independent owner-operators and fleet drivers, leave their engines idling for three main reasons: weather conditions, economic pressures, and old habits. In cold weather, a truck's engine and fuel tank need to stay warm.

How long should a diesel idle before driving?

The best thing you can do to warm up your diesel engine—after letting it idle for no longer than two minutes—is to start driving it. Heading off at a steady pace will heat up the engine and get the oil circulating.

Why does my Duramax idle high at times?

High idles may be commanded by the ECM for certain battery charging electrical loads or diesel particulate filter (DPF) cleaning processes. These idle up speeds may occur with no input from the customer.

What is the purpose of high idle for diesel?

For those who idle their trucks for long durations (tradespeople, whatever) it keeps the oil pressure and engine temps higher which is overall better for the engine.

What is high idle mode?

High idle engine switches—also called high idle controllers, or high idle kits—are used in a variety of industries in which end-users require high power from a vehicle when it's not in motion. Common applications include armored and security vehicles, work trucks, buses and motor coaches.

How often should I change my Allison transmission fluid?

Although GM recommends the Allison 1000 trans fluid and external filter be changed when the HD's oil monitor says – or every 25,000 miles for HDs used in severe service – Rod Halsten, a GM master technician in Tuscaloosa, Alabama, says let the trans fluid color and smell be the fluid-change indicators.

Will DEF ever go away?

If the DEF is stored at ambient temperatures of 75 F with no major periods of exposure to heat over 86 F then the batch of DEF will last roughly two years. If a package of DEF is exposed to periods of heating the fluid will last approximately one year.

Is the 6.6 Duramax a good engine?

As the original Duramax model, the LB7 is still extremely popular with diesel enthusiasts due to its lack of emissions control parts. In general, it's a very durable and reliable engine. However, as the first models hit the 100,000-mile mark, some issues cropped up.