Engines and Components Cylinder Heads and Components

Melling

Engine Cylinder Deactivation Delete Kit

$549.46

SKU: M00L MDK300

In Stock
In Stock
Ships by Sep 13
Free Shipping over $200
$100 Minimum Order
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The Melling MDK300 is an engine cylinder deactivation delete kit designed for GM 5.3L LC9, LH6, LMG, and LY5 engines. This kit converts Active Fuel Management (AFM) engines to a Non-Active Fuel Management system. It is manufactured in the USA.
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Part #: MDK300

Melling offers an Engine Cylinder Deactivation Kit for converting Active Fuel Management engines to a Non-Active Fuel Management engines. The Melling Deactivation Kit includes all components need to complete the changeover. Vehicle Will Not Be CARB Compliant After The Vehicles Engine Control Module/Power Train Control Module Is Reprogramed. All Melling Engine Cylinder Deactivation engine components are developed, engineered, tested and manufactured with the highest standards of quality and materials.

Features:

  • Complete, Engine-Matched Solution: Each kit bundles premium non-deactivation lifters, valley cover/block-off plugs, gaskets, and hardware engineered for your specific applicationsaving time and ensuring everything fits right the first time
  • Upgrades Reliability for the Long Haul: Replaces failure prone deactivation lifters with Melling's high strength conventional lifters, reducing risk of collapse, misfire, or the notorious lifter tick," and extending valvetrain service life
  • Restores Full Time Power & Sound: Eliminates cylinder shut off logic so all cylinders stay active under every condition, delivering smoother throttle response, a consistent exhaust note, and the full performance your V8 was built to deliver
  • Performance Ready Platform: Provides the solid valvetrain foundation required for aftermarket camshafts, higher spring pressures, and tuningunlocking more horsepower without system limitations, all backed by Melling's proven quality
  • SEMA certified 49 state compliant, for off highway only use in California.
  • Vehicle Will Not Be CARB Compliant After The Vehicles Engine Control Module/Power Train Control Module Is Reprogramed

LS AFM Delete Camshaft Kit For Active Fuel Management Engines

Vehicle Symptoms
  • Rough idle at stoplights, especially when warm
  • Engine misfire under light load or highway cruising
  • Excessive oil consumption, blue smoke from exhaust
  • Check engine light flashing or steady with misfire codes
  • Loud ticking noise from engine, especially on cold start
Diagnostic Codes
  • P0300 – Random/multiple cylinder misfire
  • P0301 – Cylinder 1 misfire detected
  • P0304 – Cylinder 4 misfire detected
  • P0306 – Cylinder 6 misfire detected
  • P0307 – Cylinder 7 misfire detected
  • P0340 – Camshaft position sensor circuit malfunction
  • P0420 – Catalyst system efficiency below threshold (Bank 1)
Relevant Conversations
  • GM 5.3 AFM delete kit for LC9 engine
  • 2010 Silverado 5.3 lifter failure rough idle
  • P0300 P0301 P0304 on 5.3 engine fix
  • Melling MDK300 install instructions
  • Do I need a tune after AFM delete?
  • 5.3L cylinder deactivation delete vs new lifters
  • What causes oil consumption on GM 5.3 with AFM
  • Best AFM delete kit for LMG engine
  • Check engine light after lifter replacement
  • How to disable Active Fuel Management permanently

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandMelling
Part NumberM00L MDK300

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