Thermostat problem?

[wyocountryboy]

So i drove my 96 PSD to work today and it never got up to the normal temp. the heater was still working and blowing hot but it my engine temperature barely got warm. could it be that my theremostat is going out or what do you guys think? thanks in advance

[justincollier]

The temp guage rarely works properly on these trucks. If it was an aftermarket t-stat, which it probably does, I have read that these stats can be up to 20 degrees cooler than factory ratings. I had to replace the water pump in my 96 about 6 months ago. I put a 203 degree t-stat from Dieselsite.com According to them, diesels run better slightly warmer. Temp gauge now reads normal. I haven't tried the heat, but I am told it will be much warmer. The stat is a bit pricey, $35 I think, but I would say it is worth it.

[parrothead96]

The thermostat in my truck started doing something similar 2-3 months ago, driving back from our property I would look at the temp gauge and it would be very low....it would almost come up to normal and then drop way back again. I figured the thermostat was about to go out so I replaced it. I used a Ford Thermostat from the dealer because of past problems with thermostats....anyway.....consider yourself lucky that the thermostat is sticking open and not closed. I would replace it sooner rather than later.