Stopped by Advanced Auto today for a cooler thermostat for the truck. They told me,they only have the stock 203 thermostat. I thought I read somewhere that 190 is the stock thermo. temp. Would mine be different because I have a 2500? If so couldn't I use a stock thermo. from a 1500? They should be the same,right? Any help is appreciated, thanks.

 

That's funny, I've put two 180* Stant thermostats into 5.7 Hemis for other people, both purchased with me present at two different Advance Auto Parts stores. You need to ask another high school dropout who works there behind their counter...

 

I have an 03 and my thermostat is still the stock. My coolant temp levels off at 203 F. I didn't think that would be a problem unless you are racing the motor for long periods of time, but every day driving and getting on it every now and then. Hauling and everything else. Haven't had any temp fluctuations. Only reason you want it to be cooler is if the temp rises for you, then the cooler thermostat is to allow the radiator to get coolant sooner to help keep the temp down lower for a longer period of time. The engine will still get as hot as it can get. At most, sitting in traffic for hours on a hot summer day down here in Atlanta, GA; the temp of my truck got at most 206. I got a digital coolant temp gauge and data logger(not a programmer) that I use on my truck. My little race car it was on had to go to the scrap yard, so I keep them to good use.

To sum it up, I don't see a problem using the stock 203 thermostat. Your choice tho. Oh, make sure you don't get one that opens before you go into closed loop operation which is the temp required for the engine to come off of a default warm-up programming and starts using the O2 sensors for proper performance. Usually 180-190 degrees for most vehicles.

 

Im with you

 

But isnt the engine designed to be happiest at 203'f? Cooling it down will enhance the longevity of certain components, but the truck wont run at peak effiency at lower temperatures.

what are your reasons for changing to lower t-stats?

 

Got Mitch makes a great point. Your truck is meant to be operated at a certain temp.
But if you want to get on that subject why add a CAI, The stock box is set up for your truck.
Why add a Cat Back Exhaust your truck is set up to push exhaust gasses out of a stock system.
We do it to see if HP?TRQ gains are found and for the love a turrnin wrenches on our trucks.

I have personally never seen a lower thermostat Dynoed...... so lol

 

And I'm gonna continue doing it until I can get them front tires off the ground.

 

I put in a 180 degree t-stat a while back. I could feel the difference. But living in the Rockies I'm gonna put the stock t-stat back in around the end of October cuz it gets real cold here. From what I understand, the engine has to run at a certain temp to burn off carbon deposits. Fortunately for me I rev my engine a lot when I'm driving. I'm always gunning it and rolling high rpm's. So I'm blowing a lot of that junk out.

 

Ive been running a 180 for the longest and no complaint from my truck. Anyone who is close enough to ride with me would certainly have a grin on their face after getting out

 

Lol thats the goal pullin the wheels off the ground or impressing are friends!!
But since ive put mine in ive had no problems and this Texas heat sure does take its toll on a motor so i figured a couple of degrees of cooler water would be ok