Duramax Head Stud Kit 2001–2016 6.6L LB7 LLY LBZ LMM LML — Fits ARP 230-4201 — Heavy Duty Parts Co.

Duramax Head Stud Kit 2001–2016 6.6L LB7 LLY LBZ LMM LML — Fits ARP 230-4201 — Heavy Duty Parts Co.

Clamp your heads down and keep them there. Built to hold the boost long after the factory bolts have given up.

Heads up: This is the Heavy Duty Parts Co. head stud kit — our own take on the popular ARP 230-4201 setup. It is a direct-fit alternative built to the same job, not a genuine ARP product. The ARP part number is listed for cross-reference and fitment only.

The factory torque-to-yield (TTY) head bolts are the weak link in every Duramax. They’re stretched past their yield point from the factory, they can’t be reused, and the second you add boost, fuel, or timing they start letting the heads lift — which is how head gaskets blow. This complete head stud kit replaces those bolts with through-hardened studs that deliver dramatically more consistent clamping force, so your heads stay sealed under the kind of cylinder pressure that destroys stock hardware. Studs also pull a truer, more even torque load than bolts, and unlike the factory TTY hardware, they’re fully reusable on your next teardown. This kit fits the 2001–2016 6.6L Duramax (LB7, LLY, LBZ, LMM, LML) only — it does NOT fit the 2017+ L5P, which uses a different stud setup. Verify your engine code before ordering.

Technical Specifications

• Condition: Brand New
• Application: 6.6L GM Duramax Diesel
• Material: Premium Chromoly Alloy Steel
• Tensile Strength: 180,000 PSI
• Thread Process: Rolled after heat-treat
• Hardware Included: 12-point nuts & parallel-ground washers
• Finish: Black oxide
• Sold As: Complete head stud kit for both cylinder heads
• Reusable: Yes — not torque-to-yield
• Cross-Reference: Direct-fit alternative to ARP 230-4201 (fitment reference only)

Fitment Data

Common Applications:

• 2001–2004 Chevrolet Silverado / GMC Sierra 2500HD & 3500HD — 6.6L LB7
• 2004.5–2005 Chevrolet Silverado / GMC Sierra 2500HD & 3500HD — 6.6L LLY
• 2006–2007 Chevrolet Silverado / GMC Sierra 2500HD & 3500HD — 6.6L LLY / LBZ
• 2007.5–2010 Chevrolet Silverado / GMC Sierra 2500HD & 3500HD — 6.6L LMM
• 2011–2016 Chevrolet Silverado / GMC Sierra 2500HD & 3500HD — 6.6L LML