Petrol/Gas B58 Overheat at Highway (Motorway) Speed

[samnt650]

Well damn, I guess I have the second case now. Very similar experience to you. Been off roading a handful of times, no overheating issues. Always try to wash all the mud off as well as I can afterwards. Then driving back home at highway speeds engine starts overheating. Light goes away the second I slow down or get off the gas. Turning the cabin heat on full blast seems to somewhat mitigate the issue. I contacted my dealer about it have not heard back from them.

When you have your truck at the shop, make sure they will test the vehicle at speed. Often dealer only do an idle test, or pressure test check for leaks. Also take pic or video showing the vehicle overheat only at speed. BTW, when did you take delivery? I got my on 12/28/23. Maybe your dealer should contact RDS (Philly) when they receive the truck.

 

[anand]

Yes all that is clean. But does someone know which is the main coolant reservoir and which is the auxiliary ? And if both reservoirs take the same color coolant?

Looks like blue cap reservoir is on passenger side and drivers side is black cap.

that

Main is blue, aux is black; both use the same coolant

 

[j3t3r]

When you have your truck at the shop, make sure they will test the vehicle at speed. Often dealer only do an idle test, or pressure test check for leaks. Also take pic or video showing the vehicle overheat only at speed. BTW, when did you take delivery? I got my on 12/28/23. Maybe your dealer should contact RDS (Philly) when they receive the truck.

I took delivery end of February. I'm getting pressure test at my local mechanic, will then try to see if I can drive it to dealer 3 hours away.

 

[samnt650]

I took delivery end of February. I'm getting pressure test at my local mechanic, will then try to see if I can drive it to dealer 3 hours away.

Pls keep us posted of your situation...

 

[anand]

I took delivery end of February. I'm getting pressure test at my local mechanic, will then try to see if I can drive it to dealer 3 hours away.

If it's overheating in any way, I wouldn't recommend driving it; historically speaking, inline 6 motors don't like to be run hot

 

[255/85]

Main is blue, aux is black; both use the same coolant

Thought I should mention that, in US petrol models, the small auxiliary radiator in the lower right bumper - the one with the fan - runs off the main circuit (blue cap) and radiator. It's the one closest to the engine. In front of that is the auxiliary radiator (black cap) for the intercooler, etc. In front of that is what appears to be the transmission cooler. The lower left bumper has the transfer case cooler.