Keeping Diesel Engine Warm

Is your grid heater working properly?

Is your intake heater working properly? That engine should start fine in the cold. I had the same truck.

Ductape wrote:
Is your intake heater working properly? That engine should start fine in the cold. I had the same truck.

It seems to be but is it something that can deteriorate and still show that it is working?

Picinisco wrote:
My dodge dually Cummins engine is very hard to start when cold. At home or camping with hookups I can plug in the block heater but what can be done when boondocking.

Describe cold, 40, 30, 0 or colder. Many times I don’t even wait for the wait to start light to go out, just crank. With full heater grid cycle starts right up!
Check out your heater grid, also how many miles!

Something is very wrong. The Cummins will start fine even without grids at temps to -20F.
It may be getting close to needing a high pressure pump and/or injectors or something else. How old are your batteries? If the ECM doesn't see a minimum engine speed during cranking it will not fire the injectors.
Rather than do anything else, I would get it looked at.

How cold is cold? As others have mentioned.....is your intake grid heater working at all or properly? We can and have “many” times started ours at -20 F. Until you get it checked-out....you may try “cycling” the grid-heater twice and then attempt a start.

As mentioned you may have a bad heater. One of the things that can/will shorten the grid-heater life expectancy, is to bring the engine rpms up (in excess of 1100 or 1200) until you see the amp/volt meter quit cycling. The drawing of excess “cold” air across the hot grid-heater, is pretty hard on it. The Dodge/Cummins manual used to warn about this!

2 things
How cold is it?
What weight of oil are you running?
Any thing after -5F you should be plug your truck in. if not the truck will knock like crazy running 15w40 oil that pretty thick for winter use if not plugging in

memtb wrote:
How cold is cold? As others have mentioned.....is your intake grid heater working at all or properly? We can and have “many” times started ours at -20 F. Until you get it checked-out....you may try “cycling” the grid-heater twice and then attempt a start.

rhagfo wrote:
Describe cold, 40, 30, 0 or colder.

You may be right. Im in southern AZ so cold is 40s and 50s.

Will replace the heater grid first.

I agree with those who say you have a problem. My 2016 Ram TDSL started at well below -20 deg on the Alaska Highway without being plugged in overnight.

(all the plugs at the motel were taken)

Thats crazy! Throwing parts at a problem without doing any troubleshooting. Check batteries first. Check air filter remove and carefully clean grid heater.
BTW your not using one of those cruddy oiled filters are you?