Then the same applies to you as well. Make sure you have bled the system well with the bleeder valve on the thermostat and be sure that OAT and HOAT were never mixed in the system.

 

My husband flushed the system and redid the thermostat, filled with new coolant, it's still overheatin, and is getting worse daily..he's very knowledgeable about cars so I'm sure he knows about the oat and hoat coolant, but we're both kinda stumped at what it could be, I took a screenshot and I'll bring it up to him! We just got this thing in July, only 55k miles on it, we were thinking water pump? There's no leaks we can see, no smells..

 

Anything can happen, but the 3.6 is not known for water pump failures whereas it's a know bugger to get all the air out of. The bleeder valve on the thermostat has tripped up many a car person before. It's not a common thing.

 

My husband said he didn't know about the bleeder valve he never had to mess with one before, so while he's at work I'm going to go get coolant and a new thermostat (just in case) what's the correct coolant for jeeps? We have been told so many different things..

 

Get one of these as well. Cheaper at Amazon than it will be locally.
Coolant burping funnel

 

This is the correct coolant for your year:

Amazon.com: Mopar 10 Year/150,000 Mile Coolant 50/50 Premixed : Automotive

Buy Mopar 10 Year/150,000 Mile Coolant 50/50 Premixed: Automotive - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

Most recommend not getting coolant for the 3.6 at the auto parts store. Many of Universal coolants are not so universal after all. Some are, but it can be hard to direct people to buy this universal, but not that so directing you to the OEM coolant is best.

Now, since you reported that you have flushed and replaced all the coolant in your system, then stick with what you already put in. Coolant these days is better to keep using the same one and not to mix them like back in the old days.

 

I am having same issue now, coolant temp is spiking into the 240s when accelerating, almost 250s. How do you get air out of the system as stated in previous posts?

 

Welcome to the forum.

^^^You tube has several vids like @Old Dogger posted above, watch about three or four and you will get a good feel on how to read your cooling system

 

There are many post on the forum on various procedures, but the simple one is park with the nose up and use the bleeder valve on the thermostat housing under the alternator. A coolant funnel will help as well. Takes a few cycles.

The correct procedure is to vacuum bleed it, but that takes a special tool.

In either case, ensure that you are using the correct coolant and that you don't have a head gasket failure putting more air into the cooling system.

 

My 2015 started this nonsense after an oil cooler change. I have replaced just about everything (even the idler pulley) and have come back to the belief that it is an oil cooler problem. Coolant flows through the cooler and if its not torqued correctly, gaskets are crappy or just a poor replacement, I could see this causing the issue. Temps around 228-240 occur at highway speed while climbing a grade. Always when the engine has been running for awhile and everything has come to temp. If I am on the flat, I oscillate between 226 (fan comes on) and goes down to 210-212, then the cycle repeats. There is not a time when the engine runs around a constant temperature.

 

How did you bleed the air out of the system after the change?

 

Yes, we see many on here that fight cooling issues that is air in the system. The vacuum flush is the best way, but it can be done with a funnel and the bleeder valve and several temp cycles. As noted, make sure you are not crossing coolants. HOAT and OAT don't play well together so make sure you only have a single type in the radiator. Some of the "universal" stuff is less universal than claimed.

It is very unlikely to be a blocked channel. The width of the gaskets is no where near enough to block the fluid ports and if the gasket did manage to come out of it's groove, it would leak. These things leak with the slightest of misalignments or gasket movement.

 

I was having the same issue for the past month and so. It got worse as the temperatures in Houston got to the triple digits. Going up 231F under hard acceleration to jump to the freeway.

What ended up working for me was the following:

Drained the system as I was running pretty much on concentrate coolant. Long story short I had a mishimoto coolant filter and I ended removing it last year as one of the hoses kept leaking. Also around April after an off road trip the reservoir bottle broke and leaked all the coolant on it. Both times I topped off the system using just concentrate, and I may have ended up with 90/10 water ratio or probably just running on 100,% coolant.

This past Saturday morning after several episodes of temperatures climbing to 235F. I decided to try something different before starting to change parts. I adjusted my blend to a 40 percent coolant and 60% distilled water. As I read somewhere in this forum that water is the best media for and effect heat exchange.

Blended all air bubbles out through the bolt on the thermostat (4 cycles to be exact) also burp the upper hose too.

Put on a brand new Mopar radiator cap.

Now I'm running max 217F (228F before). on the freeway at 75mph. My Jeep is on the heavy side with front ARB steel bumper, warn 10K winch, and off road lights on the grill also running 34's with 3.73 gears.

At iddle or traffic I'm seeing anything between 197F and 206F before it never came lower from 217F

Conclusion Jeeps seem to very sensitive to the coolant/water ratio. I think I really needs to be blended accordingly to your local/seasonal temps. Also very sensitive to air bubbles which are really hard to get out.

 

I’m having the same issue just replaced the water pump , sensor , switch out the thermostat twice, got all the air out and still temperature start elevating after hitting 65mph

 

In my case: 2014 jeep Wrangler Sahara. Temperature rose at highway speeds and passing. Replaced thermostat. Same results. Changed thermostat again with a Gates thermostat. Problem solved. The first thermostat was made in Israel and is the entry level thermostat for many different auto parts stores. The gates (made in China, which I was surprised at) is a much better quality and guaranteed for life

 

I just had this for the first time on my 2015. Never had the issue before and it caught me by surprise. I had replaced the thermostat about 6 months ago, but burped the system, seemed fine until today.

Normally, under hard acceleration or constant throttle, I would expect a waterpump issue thinking the impeller was spinning on the pump-shaft not turning enough to flow the water thru the system. But most are saying that even changing waterpumps did not help the situations.

I am going to do the cheapest thing first, burp the system again. I have replaced the oil-cooler with a billet Dorman one. I wouldn't think it is causing an issue. All fluids checked, so if that doesn't cure the issue, next will be pulling the radiator and have it boiled/checked to see if I am losing some cooling capacity due to blockages.

Is there any option for a 180 degree thermo? I looked around, haven't found one.

 

Same issue for my 2018 jeep wrangler sport 2.0. This is just coming a huge headache. First started when the ABS light would through a code and the check engine light would come on. Then it would cause the check engine light to come on when sitting at idle after a minute or so. Next the fan would come on and it ramps up at high speed over 215 - 240 and have to keep around 2rpms to not have it overheat. Then my light started dimming and shortly after that my right tire started locking up and caused issues with a brake and calibrator replacement. I bought a new thermostat sensor, radiator fan assembly, and burped and added coolant and it's persistent. It seems the only place I can get this crap is from the dealer. This is a nightmare.

 

I seemed to have fixed my issue. I did a complete flush, twice with distilled water. Left it in there the third time until It starts to get cold, but my issue seems to have been air in the system. I did remove the thermostat for a second time. Drilled two 1/8" holes in the body of the thermostat to help evacuate the air. Seems to have done the trick. I have pushed it hard in the heat, up a mountain and so far, so good. I think the small holes did the trick at getting rid of the air.

 

https://www.wranglerforum.com/threads/overheating-on-highway.2472592/?post_id=35492465#post-35492465

 

Parked right now and fan contuies to run temps slowly lowering and heater blasting though but blasting heater on freeway didn't help , the overheating light and needle was maxed

 

Welcome to the forum!

Sounds like thermostat stuck closed