Dodge Challenger Forum banner

Installing a cooler Tstat

2K views 6 replies 5 participants last post by  bigsnake 
#1 ·
TStat replacement

Changing the tstat can have significant advantages and will eliminate power lose due to heat soak if combined with an effective fan mod. This is best done with the Predator tuner. Changing the LX tstat is easy. It is best to do it when the engine is cold.
It can be done with a warm (NOT HOT) engine as long as you can touch the tstat housing without discomfort. If the engine is warm, relieve the pressure on the cooling system by slowly loosening the filler cap. When ALL pressure has been released, re-tighten the cap before proceeding.
Tools / Parts needed


You will need:
  • 13mm socket
  • Medium length extension
  • Ratchet
  • Medium sized flat blade screw driver
  • 1 gallon zip-lock bag
  • The appropriate thermostat
Removing the thermostat

  1. First, open the hood. You will see the tstat housing to the right (car right, your left as you face the front of the car) and below the intake. DO NOT REMOVE THE FILLER CAP UNTIL YOU ARE DONE AND READY TO REPLACE FLUID!
  2. Open the zip-lock bag and place it under the tstat housing, it will lay there if you place it right. Slowly loosen the tstat housing bolts. When the coolant starts to seep out, grab the zip-lock and place it under the housing while jiggling the housing. You should be able to catch most of the coolant and avoid making a mess. Finish removing the housing and place the housing, still attached to the hose, aside.
  3. While holding the zip-lock bag under the now exposed tstat, pry out the tstat with the screw driver. Again try to catch the coolant that will leak out.
  4. If you have removed the filler cap, hurry up and replace it as you will now lose all of the coolant above the tstat opening!
  5. Remove the gasket from the OEM tstat.
  • . If you have one of several 170*-180* replacements you will have to try the fit and perhaps file or grind some off of the O.D. to fit.
  • OK so you now have the tstat "fit" that you need.
Installing the new thermostat

  1. Place the gasket onto the new tstat and gently press the tstat into the recess, do not force it. If necessary remove more material from the O.D. to achieve a slight interference fit. Make sure that the tstat is facing the correct way. (it should be marked) Also, if the new tstat has a jiggle pin/bleed hole, position it to the top.
  2. Replace the tstat housing
  3. NOW you can open the filler cap and replace the coolant you saved in the zip-lock bag.
  4. Replace the filler cap, start up the Hemi and check for leaks.

Gaskets

If your gasket is damaged during installation, replacement gaskets can be found at the local Carquest Auto Parts store. They are not included with the thermostat.
Carquest part #C31788
 
See less See more
1
#6 ·
I thought I saw somewhere in a post where someone said that after changing the tstat you need to do a predator tune or else the car wouldn't recognize the new lower temp. Is this true or does that only apply to older models?
The fan speeds will need to be lowered to get the full benefit of the 180 T-Stat... that being said it only can be done on 08-10s!
 
#7 ·
The fan speeds will need to be lowered to get the full benefit of the 180 T-Stat... that being said it only can be done on 08-10s!
That's a fact Jack! Without the predator to adjust the fans you won't get much benefit. :smileup:
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top