thermostat
 

wanted to change the thermostat on my 5.3 to lower the temp. i saw one that lowers it down to 180 and another lowers it down to 160. any one change theirs to a lower one.. any problems, concerns, perform better. anything???

You dont wanna go lower than 180. The computer is set to reach 176 and then run closed loop. Running lower than that will run open loop and you will just be using more fuel by default cuz the computer still thinks it needs to warm up. Plus these motors run great at 190. Only reason why a lot of people run it cooler is cuz they get custom tunes to advance timing. This causes more heat and run the risk of pre detonation if the cooling system is not working good. Instead of spending 40 bucks for a new thermostat to run cooler, you can modify your stock t-stat and make it close at 180. Thats what I did.

Mine was busted on my 92 and I just replaced it with a 180 yesterday. The old one was so loose it sure explained why my temp guage never got above 120. All I did was take out two bolts, take out the old one, then put a new gasket on the new one and sealant and popped her back in there.

My 180 degree stat was $6.99 at autozone, not $40. I figured that a motor with 148,000 miles on the clock didn't need to run at 192 degrees anymore

I know that one can get a 170' temp stat now im running a 160 only because of my chip. Also I just found out not long ago that they have fail safe stat's if they mess up they just stay open instead of closed and over-heating your engine.

Lockup stat
 

I have had a lockup t-stat in my 94 350 for 3 or 4 years now. It works very well truck over heated a week ago and after it cooled and the coolant returned to the radiator I drove home.

Mine was 40 bucks cuz on the 5.3 you just dont buy the stat, you have to buy the housing too. Its all one piece. To run a lower temp you pay more money.

What brand are you looking at? I have been thinking of doing this to.
I work at a parts store and get stuff really cheap ! I was looking to see what brands is the forums recommendation?