Yeah it does seem to run hot for whatever reason. I have a 2014 5.7 summit I bought new and have always noticed this also. I was climbing some very steep grades in west virginia few weeks ago and it touched 244 at times which to me sounds to high if not towing anything. Wonder what that would have been if towing near the 7200lb limit lol

 

Thanks for the reply. It is reassuring that others with the 5.7L are experiencing the same thing. Probably normal for this vehicle. LOL is right regarding the 7200 lb limit. I have a trailer that is just over 1,000 lbs and I took it out a couple times last summer and the oil temp held pretty steady on an interstate with some moderate hills. But I didn’t really challenge it with a low speed climb. I probably should pull it up this grade near my house on a hot day just to see how high the oil temp gets.

I experienced temperature issues with my previous GC (2008) too. I pulled a 3,500 lb trailer for a while with it, but had to eventually downsize the trailer because I was always worried about the rise in engine temp on hills – even the moderate hills on the interstate. It didn’t have an oil temp gauge, so I can’t really compare it to my 2019. I do have to say that if I didn’t have the digital oil temp gauge on the 2019, I probably wouldn’t be obsessing about it as much.

 

I have a 2019 Trailhawk with the 5.7L. Lately I've become concerned about the oil temperature, and despite reading several other posts on that topic, I'm not sure if what I am experiencing is normal or a sign of trouble.

Normal temp at highway speed is pretty consistent at about 213 degrees. But when going up a fairly steep grade averaging about 35 mph, it is getting up just over 230 degrees. Not towing anything. And that is at a pretty moderate ambient temperature of under 70 degrees. I worry what it will get up to when it is 85 degrees outside.

I live at elevation 7000 feet, and the fairly steep drive I mentioned is going up to an elevation of 9000 feet. I wonder if the high elevation is making my oil temperature go up more so than others who have posted on this topic. I have only had the vehicle for a year, so haven't yet decided what is normal. I'm pretty sure that it is running higher than it was last summer, but I could be wrong about that. I do use a full synthetic oil.

Elevation must have an effect on the Hemi's as when I came home from skiing over Loveland Pass (11,991'), many times this last season, my oil temp would hit in the 250's, note I was in sport mode, but this would be the only time I'd seen it in the 250's. Seldom have I driven in rush hour traffic, but the few times I do, I see elevated temp's, but not like I see at high elevations.

 

Going up steep grades makes the engine work harder.
Add to that the higher the altitude the less denser the air which could translate into less engine power and cooling.
Myself, I'd only worry about the coolant temperature and not so much the oil temperature.
I'd guess if the PCM detected a dangerously high oil temperature it would throw a CEL or alert the driver with a message.

This is one of the reasons car companies prefer to use idiot gauges instead of real time gauges.
Idiot gauges keep their customers fat, dumb and happy that is until the CEL turns on.
My F150 has real time gauges except for the oil pressure which is basically a trickster idiot gauge which never leaves half scale whether at idle or WOT.

 

Thanks jgcrp1 and moparado for the replies. It does really seem to me that elevation makes a big difference, and that was the case too with my 2008 (also a 5.7L). Back when I first started having concerns about engine temps with that vehicle, when pulling a trailer, a mechanic told me that elevation is a major factor. So I started paying attention to that and it did seem to be.

Based on what jgcrp1 mentioned about Loveland Pass, I think I would be a little nervous about pulling even my little 1,000 lb trailer over something like that, on a hot day. I wish I had a better feel for what temp and for how long is something to actually worry about. I’ve read articles that say synthetic oil is fine for up to 300 degrees F. But then others that say you really shouldn’t be exceeding 240 degrees. My mechanic says 240, but then I’m sure he doesn’t want to stick his neck out with a higher number.

moparado – you mentioned paying more attention to the coolant temperature. I am keeping an eye on that too, but I only have an idiot gauge for that, so it is easier to monitor changes with the oil temp. As I mentioned earlier, if I didn’t have the digital oil temp gauge, I would probably be in that category you mentioned - for now. . .

 

For temps I can tell you that when my oil was hitting 244F a few weeks ago my coolant temp and trans temp never moved from where they always are. I have never seen coolant or trans temps move in 10 years except back when coolant had air in the system from a coolant change while ago. Elevation where I saw the 244F few weeks ago was about 2400 feet above sea level so nothing crazy. I have always used Penzoil Ultra Platinum Synthetic oil, its a low cost synthetic maybe helps some if temps get high sometimes.

 

That’s interesting that your coolant temp is not going up along with the oil temp. Does your Summit have a digital gauge for coolant temp too, or a needle gauge? The needle on my coolant gauge is going up about 1/8 when the oil temp is rising from 213 normal operating on the flats to 232 after about a 10 minute drive up the fairly steep grade. Of course I have no idea what 1/8 is in coolant degrees.

I saw this discussion about oil temps in an article by “Bob’s the Oil Guy”. Not sure if Bob is a good source of info or not, but this is what he had to say:
“… Oil Sump temperature is always 1.2 to 1.43 times higher than the coolant temp. Engine oil temperatures varied with engine output and coolant temperatures varied with engine output, airflow and radiator capacity.
An interesting side-bars of the study was that the bulk oil temperature increased "only" 0.3 C for every 1.0 C increase in ambient (outside) temperatures. …”

And here is an excerpt taken from a post in this forum a few years ago that provided some good detailed temp info. Unfortunately, I neglected to capture the Poster, date, etc. and now can’t find that post again.
“I have a 2014 5.7 with heavy duty cooling & running synthetic oil. Coolant temps usually around 192-194, oil temps 205-212.
On the 5.7L, the fan turns on full at ~224°F, its thermostat temp is 203°F, with good airflow through the radiator, like moving at some speed, it typically runs a few degrees cooler than the thermostat 203°F and very hot days or with heavy loads, it might run a degree or two higher than 203°F.”

Reading this post initially got me wondering whether the highest fan speed is not working on my vehicle. But now I realize that when the Poster says “fan turns on full at ~224°F” that is probably coolant temp which would mean an oil temp of 237°F or so. I wonder if the 224°F applies to my 2019 Trailhawk? If so, then it is comforting that once I get up to an oil temp around 237 then maybe the fan will turn on high and bring the temp down a bit.

I haven’t been watching my transmission temp. The only time I really paid attention to it is when I was pulling my trailer (mostly at highway speeds), and it stayed very consistent. I will start watching it now too and see if it is going up at all as the oil temp climbs.

My mechanic uses a brand of oil that strikes me as not particularly good. I used to buy extra quarts on occasion for my previous GC and was kind of appalled when I saw what he uses. I think it was the CarQuest store brand, or something similar. Or, maybe that is higher quality than I am assuming. I wonder how much difference the brand of oil makes.

Sorry this post got so long. If you took the time to read it – thanks.

 

Thanks BradWK2 for the Pennzoil info. I might check with my shop to see if they can get Pennzoil for my next oil change. It’s a small shop, so they might be willing to let me bring my own oil. Back in the day, when I was young and ambitious, I did change my own oil. But those days are LONG gone.

Since the majority of my driving in the summer is low speed drives up to higher elevations, to get out of the heat, seems like it wouldn’t hurt to make sure I’m using a good oil and maybe changing more frequently. Thanks for sharing info with me.

 

You could always add an oil cooler. The police package hemi Durango came with an oil cooler and you can get all the parts from mopar to add basically a factory one. I added one cause towing a large trailer I’d see oil temps up around 270. Cruising around now my oil temps stay within a couple degrees of the coolant temps, oil gets to temp faster in the winter time too. I went up to Colorado last year and didn’t notice any alarming oil temps at altitude, but I wasn’t paying that close of attention. Now towing that same large trailer I see temps no higher than 240-245, my coolant temps did go up around 5 degrees but that’s a fair trade to me.

edit found the tread about the oil cooler.

2014 WK2 5.7 Hemi oil cooler addition

As many may know the late model JGC 5.7 Hemi doesn't have an available oil cooler as an option from the factory. Except...it kind of does, if you're willing to go through the effort. No, you can't use the oil cooler from the 6.4 Hemi (it won't fit properly and would be a nightmare to modify) on...

www.jeepgarage.org

 

SRTabc123 - thanks for that info on the oil cooler. Good option to keep in mind.

 

I've been doing some experimenting and found that switching to Sport mode makes the oil temp go up quite a bit. I need to experiment more, at same air temperature and driving speed, to know for sure how much. But despite that, I do like Sport mode . . .

 

I just made a run to the Walmart for some odds and ends and my temps were about what I expect for that trip. I saw coolant high of 212°, oil high of 244° and trans high of 197°. I didn’t use sport mode but have eco off in my 5.7. For the round trip which is about 90 miles I got about 24 mpg…. Ambient are temp average was 59°.

Oh I should mention that that trip involves 2 mountain passes each way, one of which is 7.1 miles of 6.7% average grade (7.1% climb only). 74% of the climb is at 5-10% grade and 5% is at 10-15%. The steepest quarter-mile is 9.3%. Elevation gain of over 2500 feet to about 10k above sea level.

 

Thanks for sharing that. I first read part of your response in my email notification and I of course assumed that a trip to Walmart would not involve steep grades. So at that point I was amazed at your temps and wondering what the heck is going on with the 5.7L temps (!?). Then I logged in and read the rest of your response, and my brain settled down.

If you don’t mind – what are your temps at highway speeds on flat terrain, and/or low speeds on flat terrain? You must have a digital coolant gauge. I’m envious.

I’m still experimenting, but it seems like going to Sport mode is causing my oil temp to go up about 5-10 degrees more, on this climb I do regularly, vs if I didn’t turn it on. But then, my tendency is to drive more aggressively when I turn Sport mode on, because that means I got lucky that day and did not end up behind slow traffic. So I need more disciplined experimenting to know for sure.
I leave my Eco mode off all the time. I hadn’t thought about whether that would have an effect on temp.

I do have to conclude, from all of the responses, that just because I am getting fairly close to 240 oil temp when I am not even towing anything, doesn’t necessarily mean there is a problem with my cooling system. But I know that when I take my trailer out and am approaching a mountain pass, there will be some sweaty palms and heart rate through the roof.

 

I don’t know if I can convince myself that it is a good thing to have the oil temp in the 240s . . . When I took my Jeep in to my mechanic a few months ago to check out the coolant system, they put on my receipt that my oil is good for up to 240, and that is a synthetic oil. At that time, I hadn’t seen my oil temp go over 230 yet because the air temps were cold.

I just looked back at some of the info I had copy/pasted from my previous online research. The people writing these articles are all over the place. The majority seem to say synthetic is good up to around 300, but there are a few that go much higher than that. And then there are some using the 240 number.

I'm also finding that the oil manufacturers don't like to give an actual number. Like the Penzoil product that BradWK2 mentioned. Penzoil says in their marketing that it withstands high temps, but I don’t see an actual number mentioned. But I see that oil talked about in articles and on blogs as being a good one, and I think it is certainly much better than what is in my Jeep right now. I do plan to change to something like that.

Holy crap, regarding your 3.6 getting up in the 280’s. Maybe that was before they started adding the oil cooler (?).

Well, I’m going to try to stop worrying about this. There seem to be many 5.7s out there that are getting up in the 240s under driving conditions similar to what I do, and life goes on for all of them . . .
I appreciate everyone who took the time to share their numbers.

 

I don’t know if I can convince myself that it is a good thing to have the oil temp in the 240s . . . When I took my Jeep in to my mechanic a few months ago to check out the coolant system, they put on my receipt that my oil is good for up to 240, and that is a synthetic oil. At that time, I hadn’t seen my oil temp go over 230 yet because the air temps were cold.

I just looked back at some of the info I had copy/pasted from my previous online research. The people writing these articles are all over the place. The majority seem to say synthetic is good up to around 300, but there are a few that go much higher than that. And then there are some using the 240 number.

I'm also finding that the oil manufacturers don't like to give an actual number. Like the Penzoil product that BradWK2 mentioned. Penzoil says in their marketing that it withstands high temps, but I don’t see an actual number mentioned. But I see that oil talked about in articles and on blogs as being a good one, and I think it is certainly much better than what is in my Jeep right now. I do plan to change to something like that.

Holy crap, regarding your 3.6 getting up in the 280’s. Maybe that was before they started adding the oil cooler (?).

Well, I’m going to try to stop worrying about this. There seem to be many 5.7s out there that are getting up in the 240s under driving conditions similar to what I do, and life goes on for all of them . . .
I appreciate everyone who took the time to share their numbers.

Almost all oil is good to 300°. Oil that doesn’t get above 210° will not last very long and is the reason you don’t want to always do short trips. You need your oil to boil out the water. There is always water/condensation getting into Your oil.

My 3.6 was a 2014 and had an oil cooler, that engine was a hellfire inferno and I just let it do its thing. My oil would be in the 260-280 range for hours at a time. I stopped worrying about it after I did everything I could think off to lower the temps. Holes in the hood, snorkels, CAI, freer flowing exhaust. Nothing made any difference. Only thing that any research I did showed was that hacking the ECM and turning the fan on full all the time does help.

I would not worry about 240° at all, normal really. I would not worry until you see sustained 260’s in the 5.7…

 

ok stumblinhorse – you are convincing, and I’m going with it. No more worrying about oil temp as I zip up the mountain (in Sport mode), enjoying the power of my 5.7L.

 

One other thing I'd throw in there is maybe don't wait until the 10k miles that the evic says before you change the oil maybe do it a bit earlier if you are always running hot. I do mine at 5k with the penzoil ultra synthetic, it's cheap priced synthetic oil so doesn't cost much more. I know the oil change is supposed to be fine to 10k but I dont remember engines burning up the camshafts and lifters like they do these days before all the thin oil and extended oil changes came out. Just a random thought lol

 

I very good thought BradWK2. Thanks.

 

My 2018 HA has Off-Road pages, and one is digital gauges.

Since this is my first Hemi, I contacted Jeep to find out what I should be looking for on those gauges that could indicate trouble. Here's what they said:

"Thank you for contacting Jeep.

VIN: XXXXXXXXXXXXXXXXX - 2018 JEEP GRAND CHEROKEE HIGH ALTITUDE 4X4

Our records indicate this vehicle was equipped from the factory with the following:
EZH 5.7L V8 MDS VVT Engine
DFD 8-Spd Auto 8HP70 Trans

Off Road Pages - Accessory Gauges

Coolant Temperature - 130 °F to 252 °F.

Oil Temperature - 130 °F to 252°F.

Oil Pressure - @ Curb Idle Speed (Min)* / 4 psi
@ 3000 RPM / 25 - 110 psi
*CAUTION: If pressure is zero at curb idle, DO NOT run engine.

Transmission Temperature - 230 °F and below.

Battery Voltage - between about 9.5 volts and about 15 volts, depending on conditions and electrical system loads.


from email - Wed 3/2/2022 11:22 AM
Jeep Customer Care <jeepcustomercare@fcagroup.com>
Vehicle Information
Signed - Joe"

That's quite a range of operating temperatures, but if you are under 230, that's the top of the range, but still within the range.

Hope that helps.
Joe

 

Thanks so much jojud11 for sharing that valuable info. I sure wish that I had a digital gauge for coolant, but I’m lacking that. Unless by chance I could access that, but don’t know how.

Yesterday I noticed that my transmission temp was up to 190 after only 10 minutes of a climb averaging around 10 mph, and that seemed excessive. But I see from the info you provided that it is well under the point of concern. I’m a worrier at heart I guess. I really like having the digital gauges, but it does invite worry in a worrier.

Thanks again.

 

Thanks so much jojud11 for sharing that valuable info. I sure wish that I had a digital gauge for coolant, but I’m lacking that. Unless by chance I could access that, but don’t know how.

Yesterday I noticed that my transmission temp was up to 190 after only 10 minutes of a climb averaging around 10 mph, and that seemed excessive. But I see from the info you provided that it is well under the point of concern. I’m a worrier at heart I guess. I really like having the digital gauges, but it does invite worry in a worrier.

Thanks again.

If you have the offroad icon on the apps screen you can find digital readouts of the coolant temp there.

 

Glad you found it. I took a pic of mine earlier yesterday and was going to show you where the digital readout was but you had already replied. Since I went to the effort anyway, here's the pic.

 

Well thanks for that effort! I hadn't noticed the coordinates and elevation display on mine. I hope I have that too. Very cool! Especially the elevation. I need to spend more time getting to know the full capabilities of my Jeep. I'm back to loving it again (for now). Thanks again.