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GMC Sierra 2500 HD Alternator

15 items

Alternator replacement is the fix when batteries keep dying, lights fade, or charging warnings appear. Get a 12V car alternator ready for daily electrical load.

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2007-2014 GMC Sierra 2500 HD Alternator 125A 12V Clockwise 6-Groove Pulley A-Premium APALT7472007-2014 GMC Sierra 2500 HD Alternator 125A 12V Clockwise 6-Groove Pulley A-Premium APALT747
A-Premium®Part # APALT747
2007-2014 GMC Sierra 2500 HD Alternator 125A 12V Clockwise 6-Groove Pulley A-Premium APALT747
4.718 Reviews
CA$208.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits GMC Sierra 2500 HD: 2007 2008 2009 2010 2011 2012 2013 2014
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
ConditionNew
item #1012W5AQ
Note
This item comes with 125 Amp/12 Volt, Clockwise Rotation, 6-Groove Pulley.
Show less
2005 GMC Sierra 2500 HD Alternator 145A 12V Clockwise 6-Groove Pulley A-Premium APALT428
A-Premium®Part # APALT428
2005 GMC Sierra 2500 HD Alternator 145A 12V Clockwise 6-Groove Pulley A-Premium APALT428
4.718 Reviews
CA$182.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits 2005 GMC Sierra 2500 HD
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
ConditionNew
item #10185C2W
Note
This item comes with 145 Amp/12 Volt, Clockwise Rotation and 6-Groove Pulley.
Show less
2007-2014 GMC Sierra 2500 HD Alternator 160A 12V Clockwise 6-Groove Pulley A-Premium APALT578
A-Premium®Part # APALT578
2007-2014 GMC Sierra 2500 HD Alternator 160A 12V Clockwise 6-Groove Pulley A-Premium APALT578
4.718 Reviews
CA$180.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits GMC Sierra 2500 HD: 2007 2008 2009 2010 2011 2012 2013 2014
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
Part interchange
‎113774, 15093928, 15857608, 15905871, 25877026, 400-12253, ADR0369, 334-2742A, 
...View more
ConditionNew
item #1003QS66
Show less
2015-2016 GMC Sierra 2500 HD Alternator 220A 12V Clockwise 6-Groove Pulley A-Premium APALT1060
A-Premium®Part # APALT1060
2015-2016 GMC Sierra 2500 HD Alternator 220A 12V Clockwise 6-Groove Pulley A-Premium APALT1060
4.718 Reviews
CA$508.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits GMC Sierra 2500 HD: 2015 2016
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
ConditionNew
item #1012WV5W
Note
This item only fits models with optional equipment.
Show less
2001-2005 GMC Sierra 2500 HD Alternator 253A 12V Clockwise 6-Groove Pulley A-Premium APALT427
A-Premium®Part # APALT427
2001-2005 GMC Sierra 2500 HD Alternator 253A 12V Clockwise 6-Groove Pulley A-Premium APALT427
4.718 Reviews
CA$216.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits GMC Sierra 2500 HD: 2001 2002 2003 2004 2005
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
ConditionNew
item #1012TGZH
Note
This item comes with 253A/12V, CW and 6 Grooves.
Show less
2015-2019 GMC Sierra 2500 HD Alternator 220A 12V Clockwise 6-Groove Pulley A-Premium APALT1221
A-Premium®Part # APALT1221
2015-2019 GMC Sierra 2500 HD Alternator 220A 12V Clockwise 6-Groove Pulley A-Premium APALT1221
4.718 Reviews
CA$360.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits GMC Sierra 2500 HD: 2015 2016 2017 2018 2019
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
Part interchange
14020N, 14020, 104210-6860, 104210-6860, 22949466
ConditionNew
item #10139GKD
Show less
2001-2005 GMC Sierra 2500 HD Alternator 105A 12V Clockwise 6-Groove Pulley A-Premium APALT549
A-Premium®Part # APALT549
2001-2005 GMC Sierra 2500 HD Alternator 105A 12V Clockwise 6-Groove Pulley A-Premium APALT549
4.718 Reviews
CA$155.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits GMC Sierra 2500 HD: 2001 2002 2003 2004 2005
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
ConditionNew
item #1003QYVA
Note
This item comes with 4 pin plug, Not 2 pin.
Show less
2006 GMC Sierra 2500 HD Alternator 100A 12V Clockwise 6-Groove Pulley A-Premium APALT1134
A-Premium®Part # APALT1134
2006 GMC Sierra 2500 HD Alternator 100A 12V Clockwise 6-Groove Pulley A-Premium APALT1134
4.718 Reviews
CA$164.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits 2006 GMC Sierra 2500 HD
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
Part interchange
11348N, 11348, 21998419, 0124325134, 0124325214
ConditionNew
item #100581ZX
Show less
2015-2019 GMC Sierra 2500 HD Alternator 150A 12V Clockwise 6-Groove Pulley A-Premium APALT1059
A-Premium®Part # APALT1059
2015-2019 GMC Sierra 2500 HD Alternator 150A 12V Clockwise 6-Groove Pulley A-Premium APALT1059
4.718 Reviews
CA$338.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits GMC Sierra 2500 HD: 2015 2016 2017 2018 2019
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
ConditionNew
item #1012X5SX
Note
This item comes with 150 Amp/12 Volt, Clockwise Rotation, 6-Groove Pulley.
Show less
2001-2006 GMC Sierra 2500 HD Alternator 145A 12V Clockwise 6-Groove Pulley A-Premium APALT575
A-Premium®Part # APALT575
2001-2006 GMC Sierra 2500 HD Alternator 145A 12V Clockwise 6-Groove Pulley A-Premium APALT575
4.718 Reviews
CA$188.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
Part interchange
8292N, 8274, 113777, 10464476, 15226003, 15754097M, 19151921, 8104644760, 
...View more
ConditionNew
item #1003R0RV
Show less
2006 GMC Sierra 2500 HD Alternator 145A 12V Clockwise 6-Groove Pulley A-Premium APALT620
A-Premium®Part # APALT620
2006 GMC Sierra 2500 HD Alternator 145A 12V Clockwise 6-Groove Pulley A-Premium APALT620
4.718 Reviews
CA$196.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits 2006 GMC Sierra 2500 HD
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
ConditionNew
item #10036WR3
Note
This item only fits the V8 6.6L model.
Show less
2007 GMC Sierra 2500 HD Classic Alternator 100A 12V Clockwise 6-Groove Pulley A-Premium APALT1134
A-Premium®Part # APALT1134
2007 GMC Sierra 2500 HD Classic Alternator 100A 12V Clockwise 6-Groove Pulley A-Premium APALT1134
4.718 Reviews
CA$164.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits 2007 GMC Sierra 2500 HD Classic
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
Part interchange
11348N, 11348, 21998419, 0124325134, 0124325214
ConditionNew
item #10058164
Show less
2007-2010 2013 GMC Sierra 2500 HD Alternator 145A 12V Clockwise 6-Groove Pulley A-Premium APALT630
A-Premium®Part # APALT630
2007-2010 2013 GMC Sierra 2500 HD Alternator 145A 12V Clockwise 6-Groove Pulley A-Premium APALT630
4.718 Reviews
CA$235.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits GMC Sierra 2500 HD: 2007 2008 2009 2010 2013
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
ConditionNew
item #1003QTSE
Note
【Note-1】This item comes with 6-Groove Pulley, rotated in clockwise with 145 Amp/12 Volt.
【Note-2】This item comes with 2-Pins, not 4-Pins.
Show less
2007 GMC Sierra 2500 HD Classic Alternator 145A 12V Clockwise 6-Groove Pulley A-Premium APALT575
A-Premium®Part # APALT575
2007 GMC Sierra 2500 HD Classic Alternator 145A 12V Clockwise 6-Groove Pulley A-Premium APALT575
4.718 Reviews
CA$188.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits 2007 GMC Sierra 2500 HD Classic
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
Part interchange
8292N, 8274, 113777, 10464476, 15226003, 15754097M, 19151921, 8104644760, 
...View more
ConditionNew
item #1003QZS4
Show less
2007 GMC Sierra 2500 HD Classic Alternator 145A 12V Clockwise 6-Groove Pulley A-Premium APALT620
A-Premium®Part # APALT620
2007 GMC Sierra 2500 HD Classic Alternator 145A 12V Clockwise 6-Groove Pulley A-Premium APALT620
4.718 Reviews
CA$196.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits 2007 GMC Sierra 2500 HD Classic
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: GMC Sierra 2500 HD
Item LocatedCanada
Quantity1
ConditionNew
item #10036Z17
Note
This item only fits the V8 6.6L model.
Show less

What does a car alternator do?

The alternator keeps your automobile alive when the engine is running, however, the battery is necessary to start your car when it is not functioning. The majority of your car's electronic parts, such as the headlights, electric steering, power windows, windshield wipers, heated seats, dashboard gauges, and radio, are powered by the alternator while you're moving or idle. All of them receive direct current (DC) electricity from the alternator. Your car's battery is also charged while you're driving thanks to your alternator.

By converting mechanical energy into electrical energy, the alternator operates. When your engine is running, it drives a drive belt that is suspended from an alternator pulley. A set of magnets is spun around a coil by the alternator's rotor shaft, which is turned by the pulley. Alternating current (AC) is produced by these rotating magnets and circulated through the coil to the rectifier of the alternator. Your car's electrical systems are turned on by the rectifier, which transforms that AC power into DC power.

How does a car alternator work?

A car alternator is a device that converts mechanical energy into electrical energy. It is responsible for charging the battery and powering the electrical systems of the car. When the engine is running, the alternator is driven by a belt connected to the engine's crankshaft. Inside the alternator, there is a stationary magnetic field and a rotating coil of wire called the rotor. As the rotor spins, it generates an alternating current (AC) by electromagnetic induction.

The output of the alternator is regulated by a voltage regulator, which maintains a constant voltage output even as the engine speed varies. When the battery is fully charged, the voltage regulator reduces the output of the alternator to prevent overcharging the battery. When the engine is idling, the alternator output may not be enough to power all of the car's electrical systems, so the battery may be used to provide additional power. When the engine is running at higher speeds, the alternator output increases to meet the demand for electrical power.

How a Replacement Alternator Supports Your Vehicle’s Electrical System

A replacement alternator converts mechanical energy from the engine into electrical energy to power the vehicle’s electrical system. It supplies electrical power to electrical components and electrical accessories while keeping the battery charged. In most charging system designs, the alternator works with a voltage regulator to maintain stable output and support direct current needs across the vehicle when the engine is running.

Bad Alternator Symptoms That Signal It’s Time to Replace

A bad alternator often shows clear symptoms: flickering headlights, dim lights, weak electrical power, and failing electrical accessories such as power windows. You may also see a dead battery even after driving, because the charging system can’t keep the battery charged. Other common causes that can look similar include a loose serpentine belt or poor connections—so it’s smart to test the alternator and belt before ordering a replacement.

How to Choose a Compatible Replacement Alternator and Order Fast

Select a replacement alternator by your vehicle’s year, model, and engine, then confirm compatible fitment and connector details. Use the page search to shop by top brands, check store stock, compare reviews and difficulty notes, and add the right unit to cart. For easier installation, verify the serpentine belt condition and access under the hood, and confirm all charging system components are in good shape before you change parts.

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Does an Alternator Charge a Battery at Idle?

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