2012 GMC Sierra 1500 Alternators

Genuine GM alternators for the 2012 GMC Sierra 1500, at wholesale prices. Alternator output rating varies by electrical load, so a truck with a tow package or upfit wiring takes a different unit. GMT900 through 2013, K2XX from 2014 to 2018, and the T1XX from 2019 with the CarbonPro bed option.

When to replace

A battery light, dimming headlights at idle, or a no-start after a short drive. On a light duty pickup, two trucks with the same badge can take different parts once cab style and drivetrain are accounted for.

What you get ordering from us

• Genuine GM only. Every alternators listing carries the original factory part number.
• Fitment checked by a person. Send the VIN and we verify the alternators before the box leaves.
• Central shipping origin. Dallas keeps alternators transit times short nationwide.
• Backed after the sale. If your alternators does not work out, we make it right.

Avoiding the wrong part

The cheapest version of a part is rarely the cheapest repair once labor is counted twice. The VIN decodes the build sheet, which is the only place option content is recorded reliably. We hold deep stock, so same day dispatch is the norm rather than the exception.