Upgrade your 2001-2016 GM 6.6L Duramax LB7/LLY/LBZ/LMM/LML with an ARP Diesel Head Stud Kit 230-4201 from SDS. It's a proven fact that OEM head bolts are the weak link in a diesel engine; especially if the engine has been modified. That's because most engines are typically assembled from the factory 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. Furthermore, because TTY bolts are yielded by design, they should never be re-used.

ARP is the industry leader when it comes to fasteners and offers heavy-duty head studs for a wide variety of popular diesel applications. Using head studs instead of standard head bolts provides your engine with the clamping force required to keep your cylinder heads from lifting and blowing a head gasket due to higher combustion pressures. For the 230-4201 Head Studs, ARP starts with a premium grade ARP2000 alloy that is rated far superior to aircraft quality alloy steels. ARP2000 is an alloy steel that can be safely heat treated to a higher level, producing a greater strength material than Chrome Moly 8740. While 8740 and ARP2000 share similar characteristics,

ARP2000 is capable of achieving a higher clamp load at 220,000 psi.

Each stud is placed vertically into special racks and precisely heat-treated. This procedure ensures complete heat penetration and is far superior to those lower quality studs from other manufacturers who just drop pieces in a basket. ARP head studs then begin a centerless grinding process to ensure that they are perfectly concentric. As many as ten separate machining steps are required to achieve this level of accuracy. The thread rolling operation is also done after the heat-treatment, which gives them about 2000% (that's 20 times) better fatigue strength than lesser studs that are threaded prior to heat-treat. It costs a lot more to do it this way, because it's tough on tooling, but the results are worth the additional effort. Fasteners are then shot-peened to remove any surface irregularities and upgrade the overall external integrity. Finally, a metal finishing process is also performed in-house with a durable black oxide coating applied for improved corrosion resistance.

There is a good reason that virtually every top professional engine builder relies on ARP head studs for their all-out competition powerplants. Simply put, there's not a better stud setup on the market today. This head stud kit is a direct-fit for the 6.6l. Duramax LB7/LLY/LBZ/I LIML engine found in Chevy Silverado and GMC Sierra 2500HD/3500HD pickup trucks and Express/Savana vans.

• Proprietary ARP 2000 Material
• Rated At 220,000 Psi Tensile Strength
• Includes Chrome Moly Steel 12-Point Nuts
• 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
• Shot-Peened To Remove Any Surface Irregularities And Upgrade The Overall External Integrity
• Hardened Parallel Ground Washers For An Even Load Distribution And More Accurate Torque Readings
• Comes With 0.50z Of ARP Fastener Assembly Lubricant