TIR0051 is a downflow radiator for the International Prostar, Paystar, 5900.
The core measures 38.5" high by 40.5" wide, 2.25" deep. It has a 2.5" inlet at the left and a 2.5" outlet at the right. The unit carries an oil cooler at the bottom grill side and no filler neck.
It replaces 12 OEM and aftermarket numbers, among them 640122, 640122PT, 2612011C1. Searching any one of them will find this part.
On radiators the inlet and outlet positions, and whether the unit carries an oil cooler, decide interchangeability more often than core size does. Two radiators with identical cores are frequently not interchangeable.
