It does appear that it starts right around 170 degrees. Going to run water over it later to see if I can manipulate it, but seems like this may be a fix.

 

My engine was notably noisier like that when at 200f before the Extinct thermo-wonder conversion. All noises were at idle and went away immediately on throttle tip in. That noise sounds familiar pre-thermostat change. Now I have a intermittent "lighter" tapping at idle which I think is a lifter. Comes and goes and fades to nothing once throttle is applied. My engine is tired at 175k but runs fine.

 

Water does seem to cool it off and stop the tick. Which i suppose is good news. Chris, the person doing the work, mentioned that acetone and ATF mixed is great for loosening rust, so I have been spraying it daily, hopefully make it go more smoothly. I do wish I had the space to do the work myself, seems fairly straightforward, thanks to your PDF write up.

 

You can drop down to a 170 degree thermostat, it will throw a cold engine code if it is a 03-04 but usually only in the winter, summer it heats up so fast it won't throw the code. You could drop down to a 160 but then even the 99-02s will throw a code. BTW, if the code bothers you , you can throw in an 99-02 ECU or flash yours with the early engine program.

 

How do you reset an ECU?

 

LR Test book, I forget the other hardware/software combo that, can do it. My guy in Greenville SC was able to flash a used ECU from an 03 to a 00, don't remember the name of the hardware.