Hello everyone,
I am trying to find out what the factory thermostat is for my 1997 Dodge Dakota 5.2 liter engine is, please? Now that we're experiencing much cooler weather here, the heat in my truck isn't that great. I think it has a 180 in it now. I'm not a mechanic, but I think that a 180 keeps the engine cooler longer. Can anyone help me, please?

Thanks,
John

 

Generally you want a 195 thermostat. You will get more heat and your fuel mileage will go up. Back before the turn of the Century, guys would put a cooler thermostat in to get a richer fuel/air mixture. That's fine for a carburetor. It's not a good idea with computers and fuel injection. You don't have a choke. To compensate, the computer goes into "open loop" mode and shoots more fuel in to warm the engine up. Since it doesn't warm up, it stays in open loop mode. I worked on a Chevy 454 once that went from 6 to 11 mpg. You have a different engine but you should see an increase in mileage.

 

It can also cause sludging, especially if you use conventional oil. Through condensation, cold engines create water that's supposed to burn off as it heats up. If the temps stay low, especially with lots of short trips, the water is retained in the oil and sludge forms.

 

Hello, sir,
I sincerely appreciate your response and help.
Thanks,
John

 

Hello, again Mr. ol' grouch,
I want to thank you again for such sound information. I did install a 195-degree thermostat in my Dakota and have noticed a big difference in heat output. I have also noticed quite a difference in gas mileage. I was amazed!!

I appreciate you, sir,

John

 

Goodness, I'm no Sir, my parents were married. (Yes, to each other.) I can't count the number of times I've seen that crop up. On nearly all the engine out there, when fuel injection came in (;ate 80's to 1990 or so) a cool thermostat will cause this. If that doesn't cure it, the timing chain is generally eat up with slack. Thermostats are cheap and easy to replace so I start with them. Guys get told by their dad, who was told by his dad that cooler air gives a denser charge. They don't generally do much mechanical work so it's obsolete information that gets passed on as "on old hot rodders trick". Sort of like holding your thumb beside your index finger rather than around the crank handle when you start a car so you don't break your arm starting it. Before 1914, that was gospel. Afterward, not so much. I don't know of any major manufacturer who still puts crank holes in the grill.

Well, I'm rattling on again. Glad I could help.

 

Definitely use a 195. Previous posts are correct. I used a 180 ( listening to my dad ) and engine light came on after a week. Code said engine temp too low. Ran rough also. Put 195 back in, solved problem.