Sinister Diesel 2004.5-2005 Duramax LLY, Heads Up Kit w/ ARP Heads – SD-HU-LLY


Product Highlights:

We’ve designed each Heads Up Kit from Sinister Diesel to add needed strength to your engine with a full set of head studs and solve one of the biggest problems encountered by owners of modified high performance diesel trucks. From the correct fasteners to the right size gaskets for your engine, Sinister Diesel helps you take all the guesswork out of strengthening your engine and protecting it against leaks that can cause engine failure.

ARP head studs are cold-forged for molecular uniformity and then heat treated before machining for a clamp load rating of 220,000 psi. With a clamping force greater than factory bolts, ARP head stud kits ensure seal integrity between your cylinder head and engine block to protect against the engine damage that can result from head gasket failure. ARP Head Stud Kits from Sinister Diesel also include nuts and hardened washers for even clamping force and accurate torque readings during assembly.

The Heads Up Kit from Sinister Diesel also include Grade C head gaskets from Mahle Motorsport that are 1.05mm thick to compensate for any material removed from the aluminum Duramax cylinder head during resurfacing. Each Mahle head gasket is manufactured to OEM specifications from multi-layered spring steal. Gaskets are stamped with beading around each combustion chamber to increase sealing pressure and then given additional polymer coatings around the oil and water passages to ensure leak-free performance and a proper seal against micro-imperfections in the head or block surfaces.

Each Sinister Diesel Heads Up Kit for the LLY Duramax engines also comes with a complete gasket set for every engine component that seals against the cylinder head including the exhaust manifold, up pipe, upper and lower valve cover, along with valve cover grommets, valve seals, and turbo drain seals.

Vehicle Fitment

2004.5-2005 Duramax LLY


  • ARP Head Stud Kit (ARP2000)
  • Grade C MLS Head Gasket by Mahle Motorsports
  • Cylinder Head Seal and Gasket Kit by Mahle Motorsports

*Special Order. Please allow for additional shipping time.

Out of stock