challenger 2002 and van

I'm presuming that it is a manual,
I find that if the ambient temp is high that the faster I go the higher the engine temp ie temp gauge rises at 110kmph but drop to 90 - 100kmph and the needle sits on it's usual spot. With that the fuel consumption goes through the roof.
Thats towing my trailer fully loaded on the Hume highway from Melbourne to Sydney.

Cheers Kev

Kev,

I think all challengers are auto?
No manuals sold.

I would also check the A/C fan.
It most probably has an electric fan to assist.
Some installations it comes on automatically as soon as the A/C is turned on, some not.

Yes, check the viscous coupling on the mechanical fan.

Checked the radiator for clogged cores or old crumbling cores?

Also find the same thing as Kev, goover a 100 km/hr and fuel consumption rises quickly, so engine must be working a lot harder.

Have a bull bar or anything in front of the grill?
Tried taking it off to see if it makes a difference?

If checked all of above, instead of a more effecient fan, how about upping the size of the A/C electrical fan, or even add one.