truck runing with very low temperature

hello every one
i have 2013 freightliner cascadia isx 2250, yesterday i was driving and suddenly check engine light came up it s spn 3060 fail18. i check it online it says something about engine cooling system monitor. i also notice when i am driving the water temperature gauge is very low it s under 150 degree usually it is above 190 when i am driving normal.
before this happen i had a problem with the coolant every 4000 miles i need to add 1 gal of coolant i look evey where i see no sign for leaks ,i took it to a shop they check it with air pressure they couldn't find any leaks also
does any one has this problem before, also do i can still drive it even if the temperature is low
thx for help

 

Yes you can drive with low temp. Should be able to anyways. Just means the thermostats aren't working. If you're sure the radiator is full. Being low on antifreeze could cause a cold reading also.

I've been driving a w900 with bad thermostats for the last 2 years. Sometimes it sucks in the winter when going down hills. Gauge will drop to the bottom.

 

Get it to a cummins shop, have them see what the actual temps are, you don't want to run it with low temps too long, you will build up sludge and other problems. It may be a stuck open thermostat or a sensor.

 

I got my truck brand new and my gauge never work two years plus and still have not moved ones,

 

Get the thermostat fixed. Running cold is not good for an engine with emission controls.

 

On a related note. A few weeks ago running across Montana, it was around freezing but I observed 2 [newer] trucks already running winter fronts nearly full closed.

 

Either T-stats are stuck open or your gauge/sensor crapped out.

 

I"m gonna ask the boss about that. Since he isn't interested in replacing the stats.

 

I’d replace the boss.

 

It don't matter who you work for. It's pretty much all the same.
Money always trumps maintanance.

The only company I've worked for in almost 20 years that actually fixes things. Leases new trucks so repairs are under warranty.