Engine/Transmission (1998.5 - 2002) Thermostat

[RClark]

An acquaintance told me that he went to a higher temp thermostat-220/240 F and got better performance and mileage.

I found this hard to believe. Has anyone heard about this?

 

[Turbo Tim 1]

The story around here is to go to a lower temperature thermostat like a 180 degree.

 

[Texas Diesel]

Cummins sells ONLY a 180F for the ISB, Dodge is the one who carries a 190F. Perhaps an emission thing like gassers are getting higher than they used to be.

 

[bmoeller]

My mileage improved a bit with the 180* I put in last weekend.

 

[cumminspwr01]

Cummins does sell a 190* thermostat for the ISBs but the only application it is used in is the dodge truck. Part # 3946849 gets you the thermostat and the O-ring

 

[RClark]

I had installed a 180 thermostat 2 years ago but in these days of 2. 30 diesel fuel I was checking on something I might have missed.

 

[PRout]

I went to the 180 for a couple years, and went back to the 190 to see if there was any difference.



If anything (very hard to tell) the MPG is slightly better at 190, and might run a little smoother, but in my truck, there was no noticeable performance improvement w/ the 180.



Think the 180 may be slightly better for long term, because heat does accelerate wear.



Just some thoughts.