High oil temperature

[scarab]

I took a nice Sunday mountain canyon ride yesterday, everything was great going uphills, but I took it easy. On the way down I figured it was a perfect occasion to play with paddle shifters. I put my Jeep in Offroad plus and was going down the canyon, not using the brakes all that much, just engine braking keeping pretty high RPM and enjoyed some nice HEMI farts lol. After couple of minutes I've noticed that oil temperature went up to 268F, plus something was smelling pretty bad. Wasn't the brakes for sure and wasn't the tires. To be honest I'm not sure what that was. Coolant temp and everything else was keeping normal values all the time. Once I've noticed the smell and high oil temp I put the transmission back to auto and let the oil to cool down at lower RPM. It went back to normal temperatures pretty quickly, the smell went away and I made it home no problems. My 392 has a hair over 5000 miles on it so it's broken in pretty well and the oil is nice and fresh. I've checked the oil once I got back home and the level and smell was fine, it's not burnt or anything. Do you guys have any idea what was making that smell? I hope I haven't overcooked anything, never had any issues with my 392 before.

 

[Viking Jeeper]

268 is pretty high for oil I think. I was hoping you were almost due for an oil change and I was going to recommend a change but it sounds like you just did it. That number alone concerns me. I'am surprised it got that high because I just learned there is a oil cooler that uses coolant to keep the oil temp down.

I've never had a vehicle with oil temp gauge so I really dont have much experience with oil temps.

I have driven in mountains a lot and know to use the engine for most of the speed control on the downside.

 

[Jeepstin392]

I’m in Colorado as well. I found my oil temps are a bit higher than I’m comfortable with. However, oil needs to be at 220° to burn on the crud you don’t want. Also, synthetics are ok till about 300°.
268° is high. Considering the reduced air density at altitude, higher than average temps are also normal. My JKUR would run rather hot at altitude, I installed an aftermarket radiator, dual fans with an over ride switch and a hood vent. It took all that to get the 3.6 temps to within the ranges seen at 5500’. Anytime spent at altitude, was a struggle for heat dissipation. Hell, even grilling and cooking at altitude can be a challenge.
I’ve also smell of burning oil when decelerating for a period of a few minutes or more. As soon as I blip the throttle, it’s gone. I believe it’s blow by. I can’t find any leaks anywhere.
I’ve been researching where and how to put in some hood vents, just to get a little more air. Also, now that we understand the oil filter plenum is also a cooler, I’m looking at a remote cooler tied into either the oil line or coolant line.
with all that said, keep an eye on it. Seems to be “normal”.
when you start seeing the oil at 280°, start worrying.
the range I’ve been seeing on my rig, is 225°-258°. I once saw 264°, but I was at 13k feet.

 

[hardhat]

My coolant runs 200-225 mostly on the lower end of that scale. Oil seems to run 230 or thereabouts.
I have not paid much attention to transmission but it was 203 today. Gonna tow a 3500lb camper next month and will watch temps and see what they do. Seems like the transmission temp is higher than it should be for regular driving. Is the transmission oil cooler cooled by coolant like the oil or does it have an air based heat exchanger?

 

[Mandrake]

Glad I found the oil temp thread. Only if the outside temps stay in the 30's or low 40's (Fahrenheit), does the oil temp stay below 225 in stop and go or parking lot driving. I see 231 regularly if you drive through a residential neighborhood and just off idle @ 25mph.

Highway 55-60 coolent will stay round 205-207 even in the summer. Oil goes up to 225 and hangs around there as long as you have air coming in the grill. You slow down at a just one stop sign and its 231 !

I'd like to put the coolent fan on a manual switch. Maybe one of my aux switches? Get that fan running early when in slow motion to pull in some air.

So 230 is about normal for oil Temp in this wrangler? I leave it on the offroad pages gauges most the time . I am addicted to that display. I always use it in my Challenger. That was one of the first things I checked for in the 392 wrangler.
Now the 392 oil temp in my Challenger runs about 25 degrees cooler. But its motor was not shoe-horned in place

I have 1350 miles, and was thinking about changing that oil for the first time. Seems consistent, on temps I'm watching it closely.
best regards
M

 

[Firedude]

I experience higher than I like oil temps in the summer( upper 240's lower 250's) To keep them in check I use the Tazer to turn fan on. Brings temps down in a few minutes.

 

[Leftfield]

I took a nice Sunday mountain canyon ride yesterday, everything was great going uphills, but I took it easy. On the way down I figured it was a perfect occasion to play with paddle shifters. I put my Jeep in Offroad plus and was going down the canyon, not using the brakes all that much, just engine braking keeping pretty high RPM and enjoyed some nice HEMI farts lol. After couple of minutes I've noticed that oil temperature went up to 268F, plus something was smelling pretty bad. Wasn't the brakes for sure and wasn't the tires. To be honest I'm not sure what that was. Coolant temp and everything else was keeping normal values all the time. Once I've noticed the smell and high oil temp I put the transmission back to auto and let the oil to cool down at lower RPM. It went back to normal temperatures pretty quickly, the smell went away and I made it home no problems. My 392 has a hair over 5000 miles on it so it's broken in pretty well and the oil is nice and fresh. I've checked the oil once I got back home and the level and smell was fine, it's not burnt or anything. Do you guys have any idea what was making that smell? I hope I haven't overcooked anything, never had any issues with my 392 before.

I've fretted a bit about the higher oil temperatures, especially when out on the trail in 100F temperatures. I've seen similar temperatures. I've been researching the same issue and found that its hard to come up with reasonably sourced information, but here's the best I've found:

An article from Motor Trend on oil temperatures: https://www.motortrend.com/how-to/engine-oil-temperature/

In a nutshell:
1) Engine oil needs to be at least 220 degrees F to burn off all the deposits and accumulated water vapor
2) A full-synthetic oil will withstand sump temperatures in excess of 300 degrees
3) A high-end engine is built as a total combination. Piston-to-wall clearances, piston ring end-gaps, and bearing clearances are specifically tailored to match the engine oil's characteristics and intended operating temperature

A nice Q&A addressing concerns about oil temperature, from the Porsche Club of America site: https://www.pca.org/tech/engine-oil-temperature-during-hpde

PCA Tech nutshell:
1) Director of GT4 ClubSport development that indicated the Porsche was not concerned with oil temps as high as 290F
2) Blackstone lab results show oil analysis and wear indicators remain within normal oil change parameters

So I'm trying to get used to the idea of higher temperatures. Our synthetic 0W40 oil is a pretty robust lubricant for the 392:
0W: The oil gets no thicker than 0 weight at the cold temperature (Winter) spec
40: The oil gets no thinner than 40 weight at the standard operating temperature spec

This means the oil retains its viscosity characteristics over a wide operating temperature range; or specifically to this question - it acts like running 40 weight for our high temps.

I'd love to see results if anyone has sent a sample into Blackstone. I tow and off-road quite a bit during the summer - I'll try to capture a sample if no one has already done it by then.

LF

 

[Mandrake]

Cool , Great information. I will continue to use or Pennzoil 0W-40. Yeah I tazer idea is good for starting that fan earlier.
Thanks for that,
Good stuff. I already had a bunch of the larger Mopar filters bought for my Challenger's 392, so I can use them on the Jeep's 392.
maybe a bigger oil cooler?

 

[Ted392]

Cool , Great information. I will continue to use or Pennzoil 0W-40. Yeah I tazer idea is good for starting that fan earlier.
Thanks for that,
Good stuff. I already had a bunch of the larger Mopar filters bought for my Challenger's 392, so I can use them on the Jeep's 392.
maybe a bigger oil cooler?

Oil cooler is built into the oil filter housing. It is wet to wet. Making it bigger? I don't think is an easy change/mod.