TMR0003 is a downflow radiator for the Mack CHN, CHU, GU Granite, model years 2008 to 2010.
The core measures 39.125" high by 35.125" 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 and no filler neck.
It replaces 59 OEM and aftermarket numbers, among them MAC28, 21095130, 21504554. 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.
