Bustedback

Take the infrared temp gun and start at the top of the radiator and work your way down. There should be a big difference between the top and bottom.

5-90

If it were a vertical-core radiator, I'd agree with you. But, this is a cross-flow job. Higher temperatures should be found near the tank where the thermostat housing is plumbed, lower temperatures on the "suction" tank (water pump hose.) I think the temperature should show a slight decrease as you go top-to-bottom, but a more significant decrease pax-to-driver side.

Remove the grille before reading temperatures, as it can interfere with readings (the IR gun reads the plastic grille, instead of the radiator core.)

dave1123

In my experience, a contact thermistor works much better.

5-90

It do, but most people don't have those - and you still want to remove the grille to access the radiator core (unless you like dodging fan blades! I do not.)

dave1123

Why not check temps at the tanks? Seems logical to me.

5-90

Checking temps at the tanks will help you find out that the radiator is working - overall.

Checking gradients across the core will tell you if flow is blocked - and where. Checking the tanks won't do that.

mrtoofast4u

The radiator is brand new and flowing.