1998.5-2023 Cummins 24V 5.9L/6.7L ARP Custom Age 625+ Head Stud Kit

It's a proven fact that OEM head bolts are the weak link in a diesel engine; especially if that engine has been modified for increased performance levels beyond OEM specifications. That's because Duramax, Cummins, and Power Stroke engines are all assembled using 'Torque To Yield' (TTY) bolts and preloaded to yield and beyond (typically 100-110%). Any increases in combustion pressure can lead to problems like blown head gaskets or catastrophic engine failure. And because TTY bolts are yielded by design, they should never be re-used.

ARP solves the problem by offering stronger head studs that are designed for higher clamping loads. They are available in two different strength materials to safely handle applications from performance street (ARP-2000) to all-out competition (Custom Age 625+).

This newly formulated Custom Age 625+ super-alloy demonstrates superior fatigue cycle life, tensile strength and toughness – with complete resistance to atmospheric corrosion and oxidation making it best suited to extreme, high horsepower competition builds on 24V Cummins 5.9L and 6.7L engines manufactured from 1998.5-2018. ARP studs are heat-treated prior to thread rolling and machining to provide optimum fatigue strength. 12-point nuts and hardened parallel washers included for even load distribution and accurate torque readings.