Winter Operating Temps 6.4

[DonnyC]

Not sure of winter is actually here yet…. But I’m curious what the normal operating coolant temperatures are for a 2014 2500 6.4 during the cold season.

When it gets down to about 30 and a little colder the truck will fluctuate between 226 then shoot to 195. Usually when I’m driving with the cruise control on around 65 and I give it some gas it will go from 210 to around 185 sometimes 175. I understand that the water pump is moving more water but the temp difference seems extreme…

Before the season started my truck wouldn’t get to temp and during the winter time would stay at 175. I have since replaced the ECT sensor and the thermostat. Now it gets up to temp and stays warm.

I’m not towing or hauling anything when this happens, just curious if this is normal or if I possibly have a bad water pump or something along those lines.

Thanks!

 

[Tulecreeper]

You may want to ask someone in the 4th Gen forum as things may have changed with the engine between years.

 

[68PowerWagon]

My 2016 would do something very similar except it would not get any warmer than about 200-210 which is where these newer gas engines run now. It was almost like the coolant system was larger than the truck actually needed. Once that thermostat opened up you could see the temp drop dramatically to the 175-185 as you mentioned. The original thermostats had issues. I bet more than half the 4th gen owners had to change theirs within the first 3 years. Rumor had it that these engines were not cleaned out completely and some casting sand was left behind. Thus causing heater cores to get plugged & maybe this was part of the issue with the thermostats as well.

 

[Ratman6161]

Not sure of winter is actually here yet…. But I’m curious what the normal operating coolant temperatures are for a 2014 2500 6.4 during the cold season.

When it gets down to about 30 and a little colder the truck will fluctuate between 226 then shoot to 195. Usually when I’m driving with the cruise control on around 65 and I give it some gas it will go from 210 to around 185 sometimes 175. I understand that the water pump is moving more water but the temp difference seems extreme…

Before the season started my truck wouldn’t get to temp and during the winter time would stay at 175. I have since replaced the ECT sensor and the thermostat. Now it gets up to temp and stays warm.

I’m not towing or hauling anything when this happens, just curious if this is normal or if I possibly have a bad water pump or something along those lines.

Thanks!

Mine is a '22 so I don't know how differ3nt my engine is from yours. But mine runs at aboutnthe same temperature year round and regardless of conditions. I.e. if I was out last week with the sub zero temps, once wormed up the coolant temp would be about the same as if I was towing my travel trailer on a 95 degree summer day.

 

[2003F350]

As much as OP's truck is fluctuating, I would say he's got a cooling issue. On my old '17 I never saw much over 215 once up to temp, and never saw variations of almost 50 degrees like that.

Yes, the cooling system is larger than needed, but if you're getting up to 225 then a sudden drop, or dropping from 'optimal' to 20 degrees lower just by stepping on the gas, you have a flow problem of some kind, either a blockage or a bad water pump. I'd get it looked at.