Caterpillar 1D4595 Cap Screw High Head

The Caterpillar 1D4595 is a high-head hex cap screw designed for cylinder head fastening in heavy-duty diesel engines. Manufactured to SAE J429 Grade 8 (ISO 10.9) specifications, the fastener features a 5/8-11 UNC thread pitch, 6-inch (152 mm) overall length, and 0.48-inch (12.22 mm) head height. The steel body receives a phosphate and oil coating for corrosion resistance and consistent clamp load retention. This cylinder head bolt serves as a direct replacement for Caterpillar OEM part numbers 1D4595 and 1D-4595. It is engineered for compatibility with Caterpillar 3304, 3306, 3406, C18, 3512B, and 3516B engine platforms. Primary applications include motor graders (120G, 12G, 12H, 130G, 140G, 140H, 143H, 14G, 14H), track-type tractors (D4H, D5H, D6E, D6H), articulated trucks (740), and pipelayers. Key aftermarket cross-references include Interstate-McBee M-1D4595, TRP 0S1566, and CTP 2H3750.