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SKU:
NLT1H00948
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2001-2004 GM 6.6L LB7 Duramax Injector Puller 6778 J-44639
$67.99
In Stock
$67.99
Sale price
$67.99
Regular price
This new aftermarket injector-removal tool cross-references OTC 6778 and Kent-Moore J-44639 for compatible 2001-2004 GM 6.6L LB7 Duramax engines.
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Compatible Models
We do our best to list all compatible models. Although this may be the part you need, your exact model may not appear below.
Compatible equipment / model
- Chevrolet Silverado 2500HD / 3500 6.6L LB7 Duramax (2001-2004)
- GMC Sierra 2500HD / 3500 6.6L LB7 Duramax (2001-2004)
- Chevrolet / GMC medium-duty LB7 applications using J-44639
- 2004 vehicles must be confirmed as LB7, not later LLY configuration
Product Overview
LB7 injectors sit beneath the valve covers and can seize in their bores after years of heat and combustion deposits. This puller grips and lifts the injector in a controlled direction so the cup is less likely to come out with it.
The tool is for LB7-style injectors and does not fit later LLY/LBZ/LMM injector layouts. It cannot guarantee that a corroded injector cup remains seated, and all exposed fuel and oil passages must stay clean.
Verify 2001-2004 LB7 engine identification, including 2004 VIN and build split, plus injector shape and J-44639/6778 reference before opening the engine.
Key Features & Performance
- Purpose-shaped puller for LB7 injector bodies
- Controlled extraction helps avoid injector-cup disturbance
- Alternative to prying against the cylinder head
- Reusable tool for complete injector service
Replaces Part Numbers
- 6778
- J-44639
- J44639
Common Uses
- Removing injectors during an LB7 replacement job
- Extracting a stuck injector without side-loading it
- Servicing injector cups and seals after proper diagnosis
Technical Specifications
- Product Type: Diesel fuel-injector puller
- Engine: GM 6.6L LB7 Duramax
- Model Years: 2001-2004 LB7
- Condition: New aftermarket tool
Installation & Fitment
- Clean the valve-cover area before opening the engine
- Cap every disconnected high-pressure fuel line
- Attach the puller exactly to the injector body
- Apply steady centered force and watch for cup movement
- Install new seals and follow injector calibration and torque procedures
Compatibility Notice
Northline Parts does its best to list all known compatible models, but the correct part may fit an application that is not shown above. Model year, production date, serial number, engine or equipment specification, installed options, and previous repairs can change fitment. Match the original part, reference number, dimensions, connectors, mounting points, and product photos before purchase.
Frequently Asked Questions
Q: Will this fit a 2004.5 LLY engine? A: No. Confirm the engine code; the tool is intended for the earlier LB7 injector design.
Q: Why avoid pulling the injector cup? A: A disturbed cup can create sealing and coolant problems and requires its own service procedure.
Q: Does the tool diagnose a bad injector? A: No. Balance rates, return flow, fuel pressure, wiring, and other tests should confirm the fault first.
Q: Is this an original-equipment part? A: No. This is a new aftermarket product. Brand names and part numbers are used only to identify compatible applications.
Part Summary
keywords: 6778 Duramax injector puller, J-44639 LB7 removal tool, 2001-2004 GM diesel injector tool, LB7 stuck injector extractor, Kent Moore J44639 alternative
Brand names, model numbers, and reference part numbers are used for identification and compatibility purposes only. Verify the original component, specifications, and application before purchase.