Mahle 42084CP Plasma-Moly Piston Ring Set for GM 6.0L LS V8 4.001" Bore

Vehicle Fitment

2004-2010 GM 6.0L Gen IV V8 LS Engines with 4.001" Standard Bore
Engine Codes: LS2, LFA, LZ1, LQ9, L76, LY6, L96

Fitment Notes

• Fits GM 6.0L LS-based V8 engines with standard 4.001" bore only
• Verify piston ring groove dimensions before purchase: 1.2mm/1.5mm/2.5mm
• For overbore applications, see 42084CP.020 (+.020") or 42084CP.030 (+.030")
• Complete 8-cylinder set included for full V8 rebuild
• Measure existing rings before ordering to confirm dimensions
• Professional installation recommended

Features

• Plasma-Moly faced top compression ring for extended life under severe conditions
• Pre-lapped rings seat immediately, virtually eliminating break-in time
• Barrel-faced compression ring contact area for efficient sealing
• CNC-controlled gap chamfer optimizes compression and reduces blow-by
• Reverse twist second ring design for better groove side sealing
• Taper race machining enhances second ring contact
• CP-20 oil ring assembly with exclusive 20-degree ear angle
• Chemical polished oil ring expander for enhanced oil drain back
• Optimized ring tension for reduced friction and extended life
• OE-quality materials and construction
• Cannot be installed incorrectly - installer-friendly design

Specifications

• Brand: Mahle / Perfect Circle
• Part Number: 42084CP
• Product Line: Mahle Original Premium Piston Ring Set
• Engine Application: GM 6.0L Gen IV V8 (LS2/LFA/LZ1/LQ9/L76/LY6/L96)
• Bore Size: 4.001" (101.625mm) Standard
• Top Ring (UCR) Height: 1.2mm (0.0468")
• Top Ring (UCR) Radial Width: 0.151"
• Top Ring Material: Carbon Steel
• Top Ring Facing: Plasma-Moly
• Top Ring Type: RF-13PFD
• Second Ring (LCR) Height: 1.5mm (0.0586")
• Second Ring (LCR) Radial Width: 0.169"
• Second Ring Material: Cast Iron
• Second Ring Type: THM-10
• Oil Ring (OCR) Height: 2.5mm (0.0984")
• Oil Ring (OCR) Radial Width: 0.123"
• Oil Ring Material: Stainless Steel
• Oil Ring Facing: Chrome
• Oil Ring Type: CP-20 (Shallow Groove)
• File Fit: No
• Gapless: No
• Quantity: 8-Cylinder Complete Set
• Warranty: 1 Year Limited
• UPC: 027067787873

Included Components

• 8 top compression rings (plasma-moly faced)
• 8 second compression rings (reverse twist design)
• 8 three-piece oil control ring assemblies (stainless steel expander with chrome-faced rails)

Product Description

The Mahle 42084CP Plasma-Moly Piston Ring Set delivers OE-quality sealing and oil control for GM 6.0L Gen IV V8 LS engines including the LS2, LFA, LZ1, LQ9, L76, LY6, and L96 engine codes with standard 4.001 inch bore. As one of the world's largest OE piston ring manufacturers, Mahle engineers these premium ring sets to meet exacting original equipment specifications while providing the durability and performance demanded by today's engine builders. The top compression ring features plasma-moly facing on carbon steel for exceptional wear resistance under severe operating conditions including high cylinder pressures and elevated temperatures. The barrel-faced contact area combined with CNC-controlled gap chamfer ensures efficient compression sealing while minimizing blow-by. Second rings utilize a reverse twist design with taper race machining for superior oil control, improved combustion gas management, and enhanced top ring stability. The CP-20 three-piece oil ring assemblies feature Mahle's exclusive 20-degree ear angle that provides the best possible side seal against the cylinder wall, while a special chemical polish on the stainless steel expander promotes efficient oil drain back to the crankcase. All rings are pre-lapped at the factory to seat immediately upon installation, virtually eliminating traditional break-in time. The installer-friendly design prevents incorrect installation, saving time and preventing costly errors during engine assembly. Ideal for rebuilds, re-rings, or performance applications where OE-quality materials and precision manufacturing are essential.