98 Ram 2WD 103K miles Recently replaced my water pump and while I was at it I replaced my thermostat. Now my water temp won't get above 170. I would blame the thermostat, but it seems to me that they either work or they don't. Yes, I installed it right side up and the box said it was a 195* thermostat. Thoughts

 

Did you test it in a pot of water before you installed it? Maybe it is stuck open. What brand was the t-stat?

 

When my truck was new it did the same thing. Only after things started to wear out did it actually move. If it stayed really low or bounced around I'd be nervous. Regular warm up and holding... I'd be glad.

 

And don't go by the factory gauge. If you are not getting nice hot heat at 170, the heater core is clogged or your blend door is not operating correctly.

 

The temp warms up and stays at a steady 170. Which I admit is not too big a problem. I think the brand name was Stant. Bought it at Advance Auto Parts. No, I didn't test it first.
I posted another thread about my heater issue. No, I don't think I am getting nice hot air. Any idea what temp I shoulde be getting? But, I was having this problem before I changed the thermostat. The water temp prior to the t-stat change would indicate about 195. That is what is puzzling.