@Pete C I have an 04’ and get P0126 in the winter with the inline stat. Since the temps are perfect for these motors I just clear the code and go about my day. Might be worth changing to a 185(which I believe is available), but since the temps are nice and cool like they should be for a V8 designed in the late 50’s, I just live with it.

 

one of my '04s has the Inline Thermostat Mod and does not throw any codes even in the coldest days of winter.

sometimes these trucks are just quirky.

 

I picked up the inline thermostat. I was thinking that while I am in there I would just replace the radiator and all the hoses. As the radiator is $320, there are some cheaper non-OEM ones out there, any issues going with one of those? What about the hose packages on places like ebay? Anyone have any experiences with those?

Currently my A/C and heat does not work, so I'd be interested to troubleshoot that while I am under the hood as well. Any good resources for that?

 

@chelskisw6 you need to start a new thread for the heater/AC issue, but it is either the fan or plugged heater core. If the fan works fine odds are it is the heater core, but there are things you can do to check.

Nissens rads work fine.

 

I did the extinct inline mod and a new $55 radiator from ebay, works so much better. Not sure you need to spend 6x.

 

URO brand seems to be one to avoid for hoses and fittings. My personal experience has been replacing URO parts in my cooling system starting around 35K miles.

My 03 D2 started with a dead engine. I had a Turner 4.6 put in there and the shop doing the work used URO parts while putting in the new cooling system. Which I've mostly replaced due to failures.

I have an inline thermostat (Extinct's) and Nissens radiator, my normal temp is 183F. I do get some temp climbing to 210+ on very steep grades with a heavy load in the D2 which is no biggie. With a low temp LR thermostat in there, I saw higher temps and greater temp fluctuations.

 

Ebay stuff is fine in the short term. Longevity is the question. I view the non-metallic components like motor oil, more frequent changes is better. Rather change every 50 or 75k than take the risk, they are relatively cheap and easy to replace.