Hey folks I got a problem. Started to get cold here in eastern PA and my truck isn't warming up. The temp gauge does not move above 140 and not too much warm air from heat or defrost. Anyone know what might be my problem? BTW this is after driving about 30 minutes to work.

 

Thermostat stuck open.

 

They are easy to replace, but expensive.

 

I would get one from Dodge or Cummins. They seem to work better than aftermarket on these trucks.

 

Cummins for sure.. Dodge if the cash is falling out of your pockets..

 

The stock stats have a rubber seal around the edge that have a habit of coming off and holding the stat open. I've removed several and just tossed the rubber. Doesn't seem to make any difference in the stat's performance.
When it's real cold it's sometimes hard to keep the coolant temp up just because of the cold air flowing though the heater coil. Probably don't even need a radiator at all in that kind of weather. Solution is to run the heater in the recirc position so that warmer inside air is flowing though the coils.

 

Try this as a experiment, get a piece of cardboard and put it between the intercooler and the radiator. IF your temps come back up to normal then you can do several things. One is to get a winter front. Another is to leave the cardboard in place. If you leave the cardboard and your temps get to high, then adjust the cardboard as needed to get your temps just right. Some guys here suggest to cut a hole where the fan clutch is so it operates normally. Hope this helps.

 

Main reason to cut a hole in the center of the cardboard is to keep the fan blades from breaking off. If there is airflow anywhere but the center of the fan every time a blade moves though the area of airflow to one without the blade flexes a little eventually causing a blade to break off and go flying, sometimes causing major damage.
In every case of a fan blade breaking off that I've come across cardboard has been involved.
Plastic fans are not effected.

 

You need to be carefull with the cardboard trick because of overtemps and head and gasket failures. Start with the t-stats and make sure the antifreeze is good and well protected for your area. Make sure you use coolant conditioner once a year to keep your ph correct etc. Eliminates a LOT of cooling system problems over the years. If you still can't get heat inside, look at the heater controls in the cab. Good luck.

Howard

 

Thanks for the replies. Thermostat - Ok so how easy to replace? Anyone have some instructions? Any directions somewhere out on the web?

 

http://dodgeram.info/tsb/1994/07-07-94.htm

 

Installed the t-stat yesterday. Took about 20 to 30 minutes. Have heat now!!
Got one from the local NAPA for 22 dollars and change. Thanks again for everyones help.