ScreaminEagle

Going to replace thermostat. Which one should I get? 180 or 190?

patdaly

Unless you are in Death Valley, I would run the 190..........

codyguy

If you live in a predominantly hot climate go with the 180, as building up the necessary heat for proper lubricity shouldn't be too much of a problem in CA, NV, AZ, TX...you get the point. But if you live in a colder climate where there is snow for more than 3 months a year, the 190 thermo is the way to go. It'll run a little hot in the summers, but heats up to provide proper running conditions when you'll need it the rest of the year.

nickg

190 so long its a cummins stat.

98fargo

I would run the 190 as well.

Diesel Dave2

I tried both...The 190 is the best...These engines are really cold blooded..

lovinCTD59

I have tried both, I prefer the 190. Engine seems to idle smoother at 190. Plus I plow snow with my truck, i need all the heat i can get when its -30F.

Bottom line, use a Cummins t stat. I had a Napa t stat fail in the mountains pullin a 48 foot enclosed toy hauler. .. I removed the thermostat and continued to the nearest Cummins house. Not a hard fix, but inconvienent to say the least.

totalloser

180 is GARBAGE, don't run it no matter WHERE you are. It DESTROYS your fuel efficiency. If you get hot with a 190 all the way open, you would get hot with a 180 all the way open.

I tried it for a while and it *savagely* ruined my efficiency. From 18/19mpg to 14mpg.

IMO the Cummins stat is superior. It fluctuates, but usually fails OPEN versus most fail closed which can cost you an engine or a big PITA. The port is also substantially larger (compared to NAPA stat). Not sure if that really matters, but it seems like it should. I ran the NAPA 190 with a filthy radiator and the engine temp would climb, the factory Cummins stat seemed to keep it under control better. Cleaned radiator and both seemed to work fine no matter the load.

I WOULD NOT RUN THE 180 though. NO benefit.

john40

I also tried a 180 thermostat and my mileage took a hit. Needless to say I re-installed the 190.
John

oldkimmer

............Is a 190 factory for a 2001............thanks,,,,,,,kim........

KATOOM

The 24v engines do much better with a hotter thermostat because the heads flow so well they need the cylinder heat.

klcammie

190 its the best for 01 24v

oldblues

hi
will a 190 stat from a 24v work / fit in a 12 valve and work properly ?

KATOOM

There's no difference that I know of.

oldblues

hi
when i talked to napa guy over phone just to try and find out if a 12v an 24v stat would interchange he said there was .100" diff in dia. and could not say if they were interchangeable ????
soooo has anyone compaired the two for fit up ????