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MAHLE 42084CP.040 Plasma-Moly Piston Ring Set Bore - 4.040 1.2mm 1.5mm 2.5mm 8-Cylinder

(Chevrolet Silverado 1500 2003-11, Suburban 1500 2007-09, Corvette 2005-08, Silverado 2500 HD 2007-10, Tahoe 2008-11, Trailblazer 2006-09 + 24 more models)

Part of: MAHLE Plasma-Moly Piston Ring Set Bore

Other options in this family: MAHLE S40564CP.030 MAHLE 41718.030 MAHLE 41787CP-030 MAHLE 41699 MAHLE 41497CP.020

Manufacturer

Picture for manufacturer MAHLE

Part Number

42084CP.040
11 reviews
Sale Price

$153.94

Estimated ship date Monday, November 23

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Product Details

The MAHLE 42084CP.040 is a premium plasma-moly piston ring set engineered for 8-cylinder engines with a 4.040" overbore (+0.040"), featuring a 3-ring configuration with 1.2mm top compression, 1.5mm intermediate, and 2.5mm oil control rings. This set is sold as 8 complete ring sets — one per cylinder — making it a full engine re-ring kit.

Key Features:

  • Plasma-moly top compression rings with MAHLE's patented HV385 thermal spray face coating over an SAE 9254 high-alloy steel base for exceptional durability under extreme cylinder pressures and temperatures
  • Pre-lapped finish allows rings to seat immediately, virtually eliminating conventional break-in time
  • Barrel-faced compression ring contact area with CNC-controlled gap chamfer for optimized compression and reduced blowby
  • Reverse-twist intermediate rings with taper race machining for superior groove side sealing and enhanced cylinder wall contact
  • CP-20 oil ring assemblies with an exclusive 20-degree ear angle for the best possible side seal in the oil ring groove, plus a special chemical polish on the expander for enhanced oil drainback
  • SAE 9254 high-alloy steel base material delivers higher tensile and yield strength, extended fatigue resistance, and increased cycle life
  • Installer-friendly design — engineered so rings cannot be installed incorrectly, saving time and preventing costly mistakes
  • Ring tension, materials, and coatings optimized per application for reduced friction and long service life

Specifications:

  • Bore Diameter: 4.040" (+0.040" oversize)
  • Top Ring: 1.2mm — Plasma-Moly Steel
  • Second Ring: 1.5mm — SAE 9254 Napier-style
  • Oil Ring: 2.5mm — CP-20 Stainless Steel 3-piece assembly
  • Ring Type: Plasma-Moly

MAHLE is one of the largest OE piston ring manufacturers in the world, supplying rings to major automakers globally. The MAHLE Original line is built to OE form, fit, and function standards, making these rings a trusted choice for engine builders performing overhauls and rebuilds on overbored engines.

Products specifications

Fits

Chevrolet Silverado 1500 2003-11, Suburban 1500 2007-09, Corvette 2005-08, Silverado 2500 HD 2007-10, Tahoe 2008-11, Trailblazer 2006-09, Avalanche 2007-09, Silverado 3500 HD 2007-10, Express 3500 2008-09, Express 2500 2008-09 + 20 more models

Piston Ring Size

.040IN

no issues. good prices. The above was automatically input for me. However I don't feel as though its accurate. The part about no issues is correct buy the prices... Well the prices really weren't good. They were the best.

Easy, Cheap prices

Site use was easy, and product shipped promptly after ordering. Price was the best I could find, would use this business again.

good price!

Great product lines good prices

It all was simple and straightforward. I hope ordered the correct parts and it comes promptly, it should help my old car a lot!

First time customer. To order is simple enough, looking for a good experience.

The item has not been delivered yet. But the email updates are great. And I found this much cheaper than elsewere.

Nice product, I relly liked these fog lights and they made a difference in visibility. The packaging was pretty good aswell for the shipping aspect.

I am a repeat customer and very happy with your products and pricing.

great price and free shipping!

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