Oil temps

[Gump]

I notice my oil temp likes to get above 250* when towing my 8000# trailer. Considering a heavier oil weight, and maybe an oil cooler. Anyone else's 5.7 get hot like that while towing? Granted I am at a 5300'-10,000' elevation with many mountain to go over, but I expected it to keep temps more under control. Coolant stays below 220*, trans rarely gets over 200*.

 

[Murphy Slaw]

Wow.

I don't have a trailer, so have no idea, but that seems pretty warm.

 

[novelmike]

My temps are similar to yours. And I am towing in temperatures of 90-105'
From everything I've read, 250 is not hot as long as you're using a good quality oil. They say you want coolant temps low and oil temps high.
Stopping for gas, or a bathroom break is the fastest way I've found to bring the oil temp down. A 10min break will drop the temp by 25'+

 

[KingTuna]

Full synthetic oils don't break down until over 300 degrees. I'd slap some Pennzoil Platinum or Ultra Platinum in that bad boy and keep on driving.

 

[Gump]

I run Amsoil fluid and their filter, so I won't worry about it. Unless it goes over 300 in which case I'll have a panic attack.

 

[JGD]

Mine normally is between 210-238° is the highest towing my boat that ive seen so far. Had me worried at first because my Jeep that I traded in for the hemi never went above 205ish really

 

[RCFiddyOne]

My temps are similar to yours. And I am towing in temperatures of 90-105'
From everything I've read, 250 is not hot as long as you're using a good quality oil. They say you want coolant temps low and oil temps high.
Stopping for gas, or a bathroom break is the fastest way I've found to bring the oil temp down. A 10min break will drop the temp by 25'+

This. As long as you are not overheating the engine, she will be fine. Most modern engines and oil are built to take temps like that.

 

[Burla]

Lower your coolant level by draining off some and putting back a gallon of distilled water. You should be using 5w30 when towing like that. I'd worry about anything past 240F.

 

[Hemissary]

Non-issue really. Stick with the recommended viscosity. Higher viscosity does not (and will never) equate to better protection.

 

[Burla]

Non-issue really. Stick with the recommended viscosity. Higher viscosity does not (and will never) equate to better protection.

The recommended weight when towing is often thicker then the recommended weight when not towing. The Manu knows something you don't?

When he is running that hot, a 5w30 would be like a 5w20 in viscosity. The hotter any metal is, the thinner the oil gets. Page 744 owners manual, they recomend 20 weight for all 5.7's, but if you have a 2500 AND are over 14k combined weight, they recommend you go heavier oil for the reason I mentioned above.

 

[Hemissary]

The recommended weight when towing is often thicker then the recommended weight when not towing. The Manu knows something you don't?

When he is running that hot, a 5w30 would be like a 5w20 in viscosity. The hotter any metal is, the thinner the oil gets. Page 744 owners manual, they recomend 20 weight for all 5.7's, but if you have a 2500 AND are over 14k combined weight, they recommend you go heavier oil for the reason I mentioned above.

The OP has a 5.7 with MDS, hence the requirement to use 5W20. Please point me to any documentation stating a (any) higher viscosity is a recommendation.

The point is - associating viscosity with bearing interface integrity versus temperature is wrong / incorrect. But it sure is a popular misnomer :^)

 

[Burla]

That isn't what I said and understand about mds, and I also know every oil guy on the board goes at least 5w30 with the mds. The OP is smart enough to know he should be showing concern at 250F. If you want to run your equipment up to 250F with 5w20, have at it. A little hotter you will have the viscosity of water.

 

[Burla]

Why do you suppose they recommend 5w20 with the 2500 until the weight is over 14k pounds? If you click the 4 on the 744 on my post on it you will see the owners manual. 5w20 for ALL non 6.4 hemi's even 2500's until you tow and weigh over 14k pounds. The manufacturer says this because they know when you are towing, thicker oil is necessary. But whatever, have at it.

 

[Hemissary]

Here are the facts:

Oil needs to reach at least the boiling point of water (altitude dependent - 100C /212F at 0ft MSL) so condensate that is present in every single combustion engine crankcase can evaporate. Normal temperature operating range for modern engines (and their tighter tolerances) is 115 to 130C (240-260F). This is all predicated on using conventional oil.

If using synthetic, 120C / 250F is seriously a non-issue.

Viscosity does not dictate bearing interface integrity but rather the rate oil moves across the interface to (as importantly) remove heat. Using a higher viscosity oil slows that rate of movement down.

Once you put away the touchy-feelie ideas associated with viscosity - only then can the facts prevail. Don't take my word for it, check the above facts for yourself.