Completely agree with you sentiments on the inline mod. Factory thermostat is overly complex to incorporate the bypass system to heat the motor quickly from cold for emissions.

I’m very confident that the Dexcool formulation you can purchase now is not the same formula that is in the lawsuit you cited. I did a bunch of Googling on it a while back and it seems like any Dexcool purchased 2010 or so will certainly not cause the same issues.

 

Inline mod is the way to go and I would keep stock fan. I heard the Hayden heavy duty fan is much louder and you will lose power

 

Interesting. While I don’t use dexcool I think that your approach (where you actually change it out regularly!) is part of what keeps your truck in good order. I have the inline mod and it looks like we both live in the PNW. With my 180 t-stat I’m running a rock solid 177-183 degrees in all weather types and driving conditions we get here. I did see 212 on a 100 degree day in Denver last summer but that was understandable. I guess ultimately when I have a 180 t-stat I expect my temps so be close to 180, if I was running at 190-200 with a 180 t-stat that would concern me a little (not that those are “bad” temps or anything). Thanks for your input despite your fear of it being an “unpopular” post!

 

Just waiting on the GlowShift inline hose attachment to add the 1/8 npt drain and all the parts will be here.
Question: When I remove the lower hose(s) with the factory thermostat, how much coolant is going to spill out? All of it? I need to know how much Prestone to buy. Thanks

 

Also, Do I want the bleeder before or after the inline thermostat? Or does it matter? I'm kinda inclined to do it after like the second pic so I don't bleed coolant all in the alternator.

 

With my inline kit from @Extinct there is no bleeder. The instructions were to just rev it to 2000 or so for a little bit. I'm not sure why that forces the air out in a way it wouldn't for the stock setup, so you might not even have to worry about "bleeding" the system anymore.

 

I use a kid’s plastic swimming pool to drain in to. It serves three functions. Blood bucket, dog bath, and coolant tray. Very easy clean up.

If you already have green coolant in there you can reuse it if the tray is clean. If you have the orange dexcool, dump it all, flush the system real good, multiple rounds until clear, and swap over to green.

EDIT: 4 jugs of 50:50 Peak Green. 3 for filling. 1 for later and top up

 

My current observations is that it is the pressurization/temperature process that bleeds the system.

Coolant temp less than inline tstat causes coolant to recirc through the heater core. Pressure builds on the closed tstat and because its the high point as it opens when the temp approaches the set point the pressure (air or coolant) relieves through the wider inner diameter of the coolant elbow reallocating the flow from the recirculating heater core loop to the main coolant loop.

The tstat because it is temperature dependant opens to relieve any excess pressure before excess pressure is built up. It almost behaves as a pressure relief valve relieving excessive pressure as the temperature fluctuates. It’s extremely predictable almost like a feedback loop. Engine on, recirculates through the heater core, pressure builds, coolant temp rises, t stat opens, pressure relief allocates recirculating coolant to the radiator through the opening of the tstat allowing thermal and pressure equilibrium post tstat.

Important tidbit in my opinion. This is why it is extremely important to utilize the tstat provided by Extinct with the precision drilled hole and to understand current operating temperatures of your truck and the outside temperature. Don’t try to drill your own hole. Just buy a backup from Extinct and always keep it in the truck. You slap a tstat with no hole the system it may run the risk of heating up excessively and the opening of the tstat requiring the system to overcome a higher temperature differential. The hole is there to allow for reduction of the pressure differential I believe. No hole, more the tstat is getting dead headed (generating more heat quickly) and excess pressure to the heater core loop and ultimately the entire cooling system. An appropriately maintain clean cooling system seems to control the temp immediately upon opening. My 180 stat starts opening at 180 and gets to 194 and immediately controls the temp at 181 in my city commute.

Get the appropriate temp tstat for your region, and ensure you have a backup so you dont have to wait for delivery and be tempted to go procure an alternative untested tstat.

Was just in the Moab Zion area last week with with 100F outside temps. With an liquid tight coolant system driving highway desert I was at max 208 driving too fast traversing hills in 3rd gear. When it was really strained in 2nd going up hills the AC condenser Fan kicked on and controlled the temp at 212. It was 104 outside. Didn’t fluctuate, controlled the temp, and performed incredibly. Before the inline mod previously I was at 210 on the highways of Wisconsin in mild mild weather.

Only observed cooling issue came from loss of pressure to the cooling system from the bolts securing the improved version 2 Carrs4x4 sight glass. After driving 1500 miles the bolts loosened and as a result the pressure didn’t build appropriately and as I mentioned previously, the optimized pressure differential from the tstat was not operating properly and my assumption was the flow of coolant within the cooling system was reduced and thus reduced cooling capacity of the system. Tightened the bolts up and back to normal operating temps and pressure. Hell, going down hill coasting in 104 outside the coolant temp closed the tstat and bypassed the tstat all together and ran at 165ish.

 

I got it all done yesterday and we drove around town and little dash down the highway. Got to 194 but would quickly come back down. It mostly hovers between 179 and 188 degrees. I'm happy with it.

 

Off topic, but I want pics of your interior.

On the in line deal, I didn’t do it, but fully support it for all the reasons everyone else has mentioned. One thing I’ll add: the OEM design was to allow for the heater (HVAC) to start working sooner so you wouldn’t have to wait as long for the coolant going to the heater core to warm up by bypassing the radiator until the thermostat opened. Neat, but dumb. The in line setup just makes it way more simple and easy to live with.

And for the record, Dexcool is the nectar of Satan.