Drop in Engine Oil Temp

[mafoo3038]

I'm hoping the video is embedded. The engine oil temp seems to drop significantly when I slow down at times. (warm at 201 then drops to 143 this time) I always have the exhaust brake on auto and only use the tow/haul when I'm towing or when I'm pulling into work (45 min drive) which is located 1/2 way down a steep hill and I don't want to burn up the brakes.

2018 3500 rfe68 crew cab long bed dually

I'm not sure if the oil temp drops all of the time or just randomly. This is my first diesel, bought it new, and I don't think that a drop in temp is going to hurt anything but I just wanted to see if anyone else has had the same issue or if this is a normal thing and I just happened to see it now?

I'm assuming that if it is a problem, I'm guessing the temp sensor isn't working correctly or there's something going on with the oil pump?

Any thoughts?

Thanks,
Matt

 

[Topzide]

@mafoo3038, Video isn't playing, shows picture of dash then goes away into nothing. Haven't noticed on mine but will watch. Remember the readings are computer generated not direct like with a gauge reading. Should be close but can jump around due to processes running thru ECM. You might want to get ALFAOBD and cable for you truck. That way you can see data from another point of view with their gauges and recorder. Alfa only works with Android and Windows OS. If you have Iphone, just get an Android tablet with a Bluetooth MX OBD reader. Allows you to diagnosis and tweak your truck! Enjoy these trucks!

 

[Newsa]

I'm hoping the video is embedded. The engine oil temp seems to drop significantly when I slow down at times. (warm at 201 then drops to 143 this time) I always have the exhaust brake on auto and only use the tow/haul when I'm towing or when I'm pulling into work (45 min drive) which is located 1/2 way down a steep hill and I don't want to burn up the brakes.

2018 3500 rfe68 crew cab long bed dually

I'm not sure if the oil temp drops all of the time or just randomly. This is my first diesel, bought it new, and I don't think that a drop in temp is going to hurt anything but I just wanted to see if anyone else has had the same issue or if this is a normal thing and I just happened to see it now?

I'm assuming that if it is a problem, I'm guessing the temp sensor isn't working correctly or there's something going on with the oil pump?

Any thoughts?

Thanks,
Matt

The engine oil temperature gauge is just an algorithm in the electronic part of the engine... probably in the power control module? There is no engine oil temp sensor that I am aware of.

 

[AH64ID]

Unfortunately the gauge is fake, just like oil pressure.

Not sure why they even bother with fake data.

 

[lpennock]

Oil Temp and Pressure are fake and not even that close to real numbers according to the external sensors I added to my CTS. Just ignore them.

 

[mafoo3038]

So since engine oil temp and oil pressure are just calculated values, does that mean using any OBD2 reader will give you the same values since there isn't a sensor in place? I don't plan on adding any sensors or anything yet until I'm out of warranty. Until then, I plan on keeping it stock.

 

[Ozymandias]

Oil temperature is almost always +10° above water temparature thanks to the powerful built in heat exchanger.

I've got a real gauge - but I wouldn't fit it anymore, there is little to no benefit from it.

 

[lpennock]

So since engine oil temp and oil pressure are just calculated values, does that mean using any OBD2 reader will give you the same values since there isn't a sensor in place? I don't plan on adding any sensors or anything yet until I'm out of warranty. Until then, I plan on keeping it stock.

OIL temp isn't available on OBD. It is not a real PID.

Adding extra sensors won't affect your warranty as long as you don't remove the stock ones. I'm with Ozymandias that I wouldn't bother with it again.

 

[AH64ID]

I ran a real oil psi and oil temp gauge on my 05. There really is no need for either. The highest I ever saw oil temp was +25° and that was towing hard and heavy on a mild built motor. Even that wasn’t close to too hot.

I do find in infuriating that FCA wants to trick us thou.

 

[josephc1]

If you need to know use an infrared thermometer and shoot it at the filter / pan. That should put you close.