Mahle 40533CP.040 Engine Piston Ring Set

Engine Piston Ring Set Overview

MAHLE piston ring set part number 40533CP.040 is a premium oversize ring set for 3.915-inch bore applications. It is built around low-friction ring technology and OE-driven engineering for engines that need controlled oil use and durable sealing.

Key Features

• Part number 40533CP.040 for 0.040-inch oversize applications
• 3.915-inch bore diameter
• Plasma-Moly face coating for improved wear resistance
• Cast iron top and second rings for stable sealing performance
• Stainless steel oil ring assembly for corrosion resistance
• Premium-grade construction focused on reduced friction and longer service life

Detailed Description

MAHLE 40533CP.040 is an engine piston ring set engineered for large-displacement Chevrolet and GMC truck, van, and Suburban applications listed in the fitment data. The ring package uses cast iron top and second rings, a stainless steel oil ring assembly, and a Plasma-Moly face coating to support consistent cylinder sealing and controlled oil consumption. The 0.040-inch oversize specification and 3.915-inch bore diameter make this set appropriate for rebuilt engines that have been machined for oversize pistons. This part number 40533CP.040 is also cross-referenced to Hastings 2M668040 and Sealed Power E217K40 for the same application.

What It Is Used For

• Restoring compression in worn cylinders
• Reducing oil consumption from ring wear
• Improving sealing after an engine rebuild
• Replacing rings in oversize-bore service work
• Addressing blow-by caused by tired piston rings

Installation Notes and Tips

Verify bore size before installation and confirm that the engine has been machined for 0.040-inch oversize pistons. Match the ring set to the cylinder finish and follow the piston ring manufacturer’s end-gap and installation procedures. This application coverage includes Chevrolet C10, K20, and GMC K2500 fitments, along with many other Chevrolet and GMC truck and van platforms shown in the fitment list.

Quality Assurance

MAHLE develops piston rings to OE requirements, with an emphasis on lower friction, reduced ring mass, controlled oil use, and extended service life. The 40533CP.040 reflects that engineering approach for rebuild-focused engine service.