How does the new 6.7L Cummins turbo-diesel handle a cold start after a deep freeze? We are about to find out.
The newly redesigned Ram has two versions of the new Cummins straight-six diesel: the standard version with 370 hp and 850 lb-ft of torque in the 2500 & 3500 HD trucks, and this high output (H.O.) version in the 3500 HD with 400 horsepower and 1,000 lb-ft of torque. While the standard diesel is mated to an updated Ram’s 68RFE 6-speed automatic transmission, the H.O. is mated to an updated 6-speed Aisin transmission.
The truck you see here is a 2019 dually 4×4 in Limited trim and with nearly every option. The final retails price on this particular truck is over $87,000.
The truck has been sitting in my driveway an entire weekend with temperatures ranging from -3F at night to 10F during the day. It was time to fire it up and go to the office on Monday morning after a -2F night, so I had to do a “cold start”. This truck did not come with an engine block heater, so it was not “plugged in” to keep it warm.
The reason a cold start test is important is because diesel fuel tends to gel or get thicker the colder it gets. Diesel engines do not like very cold temperatures.
The updated Ram heavy duty has more ways of monitoring the truck than ever before. It’s helpful to know what’s going. There is still the engine heater grid countdown counter. The engine may need up to 45 seconds of pre-warming before it attempts to start.
In this case, the engine needed about 15-20 seconds of wait time before firing. Here is what happened. Watch the video below.
If you want to watch an old 2002 Chevy Silverado HD Duramax cold start, check out this freezing comparison video below.