2016 460 temp gauge pegging at low RPM

[Mikename]

Hi all, picked up my new 2012 460 in Spokane on Friday and drove it back to Denver.

It drove great until about 3hrs left and then the temp indicator started going to max out then come back down to normal temps...

I tried power cycling it a few times, checked rad fuse 1 and 2 (fine). Eventually I figured out that if I kept the rpms above about 3750 it would keep the temp in the middle.

I’ve added a video of the temp rising when I let the rpms drop, and see it cool off when I drop down a gear and give it some rpms.



The overflow never seemed crazy hot but there are some signs of a bit of overflow. You can see it in the pic in the above post.
Anyone seen this before or have any ideas? No CEL and it never seemed to run rough.

 

[ppc]

First thing that comes to mind is the condition of the coolant and if the percentage of antifreeze was sufficient to eliminate freeze up.

 

[Tex68w]

Video no worky.

 

[r2m]

Q: why are you going 70mph in 3rd gear?

 

[ChiTown]

How many miles?
Had the water pump been replaced? If so was it recently?
Has the EGR cooler under the manifold been resealed? Was it recently?
What's the coolant level look like?
Are the upper and lower radiator hoses hot when the truck is warmed up?
Is the fan moving a lot of air?
Is the coolant red/pink?

 

[Mikename]

The problem has not happened again. I have no idea what happened but I cannot make the overheating occur on demand.

When it was overheating I let it cool nearly all the way off, but was in the middle of BFE so I figured I would try to see how I could get closer to civilization. On the way I figured out that the engine did not overheat at higher RPMs.

Mileage: 180kmi
The water pump was replaced in September of 2019
I don't know if the EGR cooler under the manifoold has been resealed, I just got it
The coolant level is slightly overful
Both hoses are hot
I have not been able to see the fan actually turn on. Is there a way to force it on for troubleshooting? The RAD fuses look good.
The coolant is red/pink.

I'm in 3rd gear at 70mph because going 4k rpm would bring the temp gauge back to normal when it was pegging at ~2k in 5th.

The most recent service was:
SERVICE: JLG - INSTALL THE AIR PUMP REPAIR KIT AND REPLACE THE AIR
DESCRIPTION: JLG - INSTALL THE AIR PUMP REPAIR KIT AND REPLACE THE AIR ~|~JLG RECALL IS OPEN ~|~T1 99 T2 99 ~|~178676 JLG001 240 INSTALL THE AIR PUMP REPAIR KIT AND REPLACE THE AIR SWITCHING VALVE

Curious if anyone else has had an intermittent problem like this?

Thanks all!

 

[r2m]

For myself, I've never had a cooling issue, but I'm only had 62k miles on the clock.