Thermostat question for you modern people

[rMetzger]

First, before we go any farther, I’m old. I’m of the generation when an engine’s operating temp was 180*F.

Period.
It seems that Shiny’s little 3L EcoDiesel has a 200* tstat.

When the OEM stat finally goes, would it be terrible to replace it with a 180, or will the computer hate it?

 

[Diesel85]

IIRC, you will need a GDE tune.

 

[BigPapa]

Stick with the original. The cooling system in your truck is a LOT different than what we grew up with.

 

[AH64ID]

The computer will not like it, your fuel economy will decline, and if you do any towing your fan won’t engage at the proper temp for the thermostat.

200° is nothing for a modern engine and 180° is too cold.

 

[Ozymandias]

Vehicle will stay in warm-up mode forever with the wrong thermostat, don't mess with it, not even a little bit like 195° t-stat or so.
Also all the engines internals are engineerd for 200°, they won't work nicely together at a lower temperature.
And you sure don't want to drive around with an engine that never reaches its operating temperature won't you.

 

[rMetzger]

Seems pretty unanimous. 200 it is. ‍

 

[rMetzger]

Seems pretty unanimous. 200 it is. ‍

Revisiting. Had a cold snap earlier this month and put on the winter-front. Warmed up to the 50s-60s and took it back off. A few days later, I got “check engine” light and the corresponding code was “too cold”. Cleared code and replaced the “bra”. Temps back to 200-ish.

 

[AH64ID]

Revisiting. Had a cold snap earlier this month and put on the winter-front. Warmed up to the 50s-60s and took it back off. A few days later, I got “check engine” light and the corresponding code was “too cold”. Cleared code and replaced the “bra”. Temps back to 200-ish.

Something doesn’t sound right. The winter front is not supposed to be used at temps that warm, you may have another issue.

 

[Diesel85]

Do you mind sharing the "too cold" code? I can look it up in the service manuals.

 

[seafish]

Something doesn’t sound right. The winter front is not supposed to be used at temps that warm, you may have another issue.

Maybe a thermostat thats stuck open?? …what else could it be ??

 

[AH64ID]

Maybe a thermostat thats stuck open?? …what else could it be ??

That’s my guess, but probably only partially stuck open.

 

[seafish]

That’s my guess, but probably only partially stuck open.

Either way it needs to be replaced if it is failing.

 

[Diesel85]

Either way it needs to be replaced if it is failing.

I agree. These here EcoDiesels need everything to be in proper working order so you don't crop up with more expensive problems.

Nip any problem with it in the bud/ASAP.

Or in other words, don't collect warning indicators like some collect baseball cards... see how many you can get before it goes BOOM!

I see too many problems with these engines mostly due to neglect or folks "trying" to make it better and not know anything about the platform or diesels in general.

These are not heavy duty diesel engines... they are light duty passenger car grade diesel engines. Huge difference in how the manufacturer wants them to operate.

 

[rMetzger]

Well, I’d like to have told you the code, but, it didn’t store as a “permanent”. T-stat does seem to be cycling, though, so I wonder if it’s beginning to fail, or if the corresponding sensor is going bad. I left one little bra hole open when it was warmer, and still not getting, and have seen it as high as 220, then cycled back down to appx 200-205.

 

[Diesel85]

Well, I’d like to have told you the code, but, it didn’t store as a “permanent”. T-stat does seem to be cycling, though, so I wonder if it’s beginning to fail, or if the corresponding sensor is going bad. I left one little bra hole open when it was warmer, and still not getting, and have seen it as high as 220, then cycled back down to appx 200-205.

Pending codes will stay until the computer decides when it's time to make it permanent per parameters, or if the fault clears itself.

Pending codes that don't trigger a permanent (meaning they come and go) are the worst to have to troubleshoot.

Plenty of shops will tell you to drive it more till it does something else, like a permanent code or it starts spewing coolant all over the place.