Description
ARP head studs replace the factory torque-to-yield head bolts with reusable, precision-made studs that deliver higher, more consistent clamping force. They are the go-to upgrade for keeping the heads sealed and preventing head-gasket failure on modified, high-boost or rebuilt diesels. Studs thread into the block by hand, so all torque is applied on one axis for accurate preload, and the block threads are spared from repeated bolt cycles.
ARP part number: 247-4205
Application: Cummins 5.9L 12v 1989-1998
Material: ARP Custom Age 625+ superalloy (approx. 260,000-280,000 psi tensile strength)
Fitment
- Cummins 89-93
- Cummins 94-98
Features
- 235k-255k psi yield strength
- 260k-280k psi tensile strength
- Custom age 625 plus super alloy
- Includes chrome moly steel 12-point nuts
- Comes with 0.5oz of arp fastener assembly lubricant
- Black oxide coating for improved corrosion resistance
- Centerless ground to ensure they are perfectly concentric
- Improved clamping force prevents cylinder heads from lifting
- Broached stud ends install & make cylinder head removal easier
- Heat-treated prior to thread rolling and machining for optimum fatigue strength
What's Included
- Head studs
- 12-point nuts
- Hardened parallel-ground washers
- ARP assembly lubricant
ARP installation instructions & torque specs (PDF)
Always follow ARP's published torque values and use the supplied ARP lubricant for accurate preload.
