





GM 6.6L Duramax LML Engine Intake Manifold
Vehicle Fitment: 6.6L Duramax LML equipped Diesel Vehicles
Part Type: Engine Intake Manifold / Intake Runner Assembly
Condition: Used
Manufacturer: GM (General Motors)
Manufacturer Part Number:
Left Hand (Driver Side): 12633292
Right Hand (Passenger Side): 12642321
Description:
This is the intake manifold for the LML Duramax. On this engine platform, the intake system consists of two separate parts (left and right) that bolt to the cylinder heads and receive charge air from the intercooler via a central Y-bridge.
Key Functions and Importance:
Air Delivery: Channels pressurized, cooled air from the intercooler into the combustion chambers.
Component Housing: Provides the mounting and sealing surfaces for the manifold gasket, sensors, and the crossover pipe connection.
Sealing: Ensures a boost-tight seal against the cylinder head to prevent turbocharger pressure from escaping, maintaining full engine power and efficiency.
Common Replacement Necessity:
Damage: Replacement is typically required if the original aluminum casting is cracked, warped, or damaged due to engine debris or improper disassembly.
Heavy Soot/Carbon Build-up: While cleaning is often possible, extreme cases of carbon or soot contamination from the EGR system may necessitate replacement to restore optimal airflow.
Key Features:
OE Fit: Guaranteed to match the factory fit and function of the driver-side bank.
Material Integrity: Constructed from cast aluminum to resist the heat and pressure of the turbo system.
Note: This is for the left or right hand intake manifold only. Gaskets are sold separately.
Notes on Condition:
Inspected for cracks, warping, or damage. May show normal cosmetic wear but is guaranteed to be functional. Gasket/seals may need to be replaced.
Fitment Guarantee: Our goal is to provide you with the correct parts and fitment for your diesel truck. If this part does not fit the engine/years specified above, let us know within 14 days of you receiving the part and we will replace it!
PLEASE READ AND FILL OUT THE WARRANTY REGISTRATION FORM TO ACTIVATE THE WARRANTY.

Supplied with every engine is a complete copy of our warranty with an attached warranty registration form. This form can also be found here. Once filled out:
Then email a copy of each document within 45 days from the time of purchase to warranty@choateperformance.com. You should also retain a copy for your records as it may be required to assist with a warranty concern.
MODEL C STANDARD WARRANTY
1 Year / Unlimited Miles

THIS WARRANTY IS WITH THE PURCHASE OF THE INSTALLATION PACKAGE AND IS FOR THE ENGINE/WORKMANSHIP ONLY. NO LABOR PAYOUTS.
EXTENDED COMMERCIAL WARRANTIES ARE NOT AVAILABLE ON WORKHORSE, CASSQUATCH RACE SERIES, OR MODEL C ENGINES.
Remanufactured Heads — 6 Months
PARTS ONLY

Cylinder heads are warranted to be free from defects in material and workmanship. This warranty does not cover cylinder heads that are damaged due to improper installation, overheating, abuse, or accident.
Short Block Engines

Warranty coverage for Short Block engines does not include labor payout. We do not cover fluid leaks on any Short Block builds.
DAILY DRIVER WARRANTY
5 Year / 100,000 Miles

THIS WARRANTY IS NOT A FULL COVERAGE WARRANTY. PLEASE REVIEW YOUR WARRANTY CAREFULLY.
Labor rate for PREFERRED DEALER ONLY is a higher shop rate using Mitchell flat rate time.
WORKHORSE SERIES ENGINE
5 Year / 100,000 Miles

THIS WARRANTY IS NOT A FULL COVERAGE WARRANTY. PLEASE REVIEW YOUR WARRANTY CAREFULLY.
Labor rate for PREFERRED DEALER ONLY is a higher shop rate using Mitchell flat rate time.
YOUR CASSQUATCH RACE ENGINE
6 Months / 3,000 Miles
PARTS ONLY

THIS WARRANTY IS NOT A FULL COVERAGE WARRANTY. PLEASE REVIEW YOUR WARRANTY CAREFULLY.
CHOATE ENGINEERING PERFORMANCE COMMERCIAL WARRANTY
1 Year / 20,000 Miles

THIS WARRANTY IS NOT A FULL COVERAGE WARRANTY. PLEASE REVIEW YOUR WARRANTY CAREFULLY.
Labor rate for PREFERRED DEALER ONLY is a higher shop rate using Mitchell flat rate time.
CHOATE ENGINEERING PERFORMANCE EXTENDED COMMERCIAL WARRANTY
3 Year / 60,000 Miles

THIS WARRANTY IS NOT A FULL COVERAGE WARRANTY. PLEASE REVIEW YOUR WARRANTY CAREFULLY.
WARRANTY COVERAGE DETAILS
This warranty will cover remanufactured Short and Long-Block engines that are built by Choate Engineering Performance unless otherwise stated. From this page on, engines will be referred to as “unit(s)” and/or “engine(s)” unless otherwise stated. Fuel pump, injectors, and turbo warranties, and warranties on all accessories, are covered by the supplying manufacturer’s warranty.
FOR PREFERRED DEALERS ONLY: LABOR RATE IS SET AT A HIGHER RATE PER HOUR UP TO A MAXIMUM OF $2,500, NO EXCEPTIONS.
THE LIMITED WARRANTY WILL BE VOID AND WILL NOT APPLY TO DEFECTS OR FAILURES CAUSED BY THE FOLLOWING:
BUYER ALSO ACKNOWLEDGES THAT PROPER MAINTENANCE PROCEDURES ARE REQUIRED TO KEEP THE UNIT IN PROPER WORKING ORDER. CHOATE ENGINEERING PERFORMANCE WILL NOT ASSUME ANY RESPONSIBILITY FOR THE COST OF THIS ROUTINE MAINTENANCE.
Buyer acknowledges the following:
This warranty will not cover damages caused by the following for remanufactured engines:
Choate Engineering Performance limited warranty will end after the expiration of time or mileage from the date of the original invoice. Any repairs or replacements will not extend the warranty. The buyer shall be responsible for all defects thereafter, regardless of cause. Choate Engineering Performance limited warranty is in lieu of all other warranties expressed or implied.
The buyer agrees Choate Engineering Performance will not be responsible for:
TO QUALIFY FOR THE 5 YEAR / 100,000 MILE WARRANTY YOU MUST FOLLOW ALL INSTRUCTIONS AND REPLACE ALL PARTS SPECIFIED.
THIS WARRANTY IS TRANSFERABLE THROUGH PRIVATE SALE AND CHANGE OF OWNERSHIP ONLY ONCE IF CERTAIN CRITERIA ARE MET.
CHOATE ENGINEERING PERFORMANCE LIMITED WARRANTY FOR THE WORKHORSE AND CASSQUATCH SERIES ENGINES IS IN ADDITION TO ALL ITEMS LISTED IN THE STANDARD WARRANTY PACKAGE AND SUPERSEDES ALL MILEAGE REQUIREMENTS.
The Limited Warranty specifically does not cover the following:
FREIGHT / SHIPPING CHARGES

CHOATE ENGINEERING PERFORMANCE SHALL NOT BE RESPONSIBLE, NOR SHALL IT PAY ANY FREIGHT/SHIPPING CHARGES.
ADDITIONAL INFORMATION

As consideration for the above warranties, the buyer agrees they will take no action, statement, characterization, or implication regarding Choate Engineering Performance that may in any manner be interpreted as disparaging to Choate Engineering Performance or the reputation of Choate Engineering Performance. Any violation of this is a material breach, entitling Choate Engineering Performance to void any warranty.


