Hey guys,
I recently did a coolant flush on my 97 3.0. While I was doing the coolant flush, I replaced the thermostat with a new one from NAPA (OE temp). The original one seemed to be working, but I figured why not swap it out while I was flushing the system anyway. However, ever since then, the truck has trouble getting up to temperature when its around say 60 degrees or below. It will just get up to where the needle points right on, or just above, the "C" on the temp gauge and stay there steady. It will only get up to operating temp if I sit idling for quite a while, but then once I start moving again it drops right back down. Of course, it's worse when it's even colder, but thankfully it gets warm enough still to get heat. I'm not sure exactly what temperature the truck gets to, but I will hook up my scan tool next time I drive and see what temp it stays at now.
Anyway, what I'm wondering is, is this normal for the 3.0 with a nice clean cooling system to run a bit colder? I believe I'd read something before about 2.3's having this issue and people blocking off their radiator with cardboard to get heat in the winter. So I'm just wondering if it is common for 3.0's to have trouble getting up to operating temp with a good cooling system. Or, if I just got a faulty thermostat. I just figured I'd ask before I go swapping out the thermostat again or even trying to test the thermostat since either way I would need to take it out.