2025+ 6.7L Cold Start Process Question

[Jmonty]

Getting our first real cold weather recently and just want to ask what's probably a dumb question about the new 2025+ engines with glow plugs and the startup process. Past experience with glow plugs in pre 2010 diesel you turned the key into on and waited for the glow light to turn off before starting. I assumed the computer would do something similar like in my 2022 where after start it would heat up the grid heater before firing. In multiple overnight cold starts in the 20's both with remote start and manual button press the engine immediately fires up with no pause/warmup etc. Is that expected? Are glow plugs now so good they are instant?

 

[Fltlander]

If you want the glow plugs to work you have to push the start button without stepping on the brake and then after the warmup brake and button.

 

[HighHP]

I have my first diesel ordered, 2026 Ram 2500 Rebel. It is due in December 16th. So for my own knowledge I looked up your question. Here is your answer.

Ram Trades Cummins Grid Heater For Glow Plugs

Since 2007, Cummins-powered Ram Heavy Duty trucks have relied on a grid heater system for cold starts, unlike their competitors, which have long used glow plugs. That changes for 2025, as Ram and Cummins have officially switched to glow plugs in their newest version of the turbodiesel 6.7-liter...

moparinsiders.com

 

[Jmonty]

So should we never remote start our glow plug based engines? The computer doesn't wait a millisecond before firing feels like it should be that smart after the grid heater based engines were smart enough to be warmed up first.

 

[superjoe83]

Glow plugs heat much faster than the grid heater, plus they are in the cylinder so the heat is right at the combustion area

 

[HighHP]

I think it safe to assume the Ram remote start programming incorporates the proper wait time for the glow plugs, regardless of what the article may say. In general both are consistent with a fast start.