Ignitions and Electrical› Charging Systems

ACDelco

145 Amp Alternator

$170.50

SKU: 20881337

In Stock
In Stock
Ships by Sep 12
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The ACDelco 20881337 is a GM Genuine Parts alternator designed as an exact replacement for your original GM vehicle's alternator. This newly manufactured unit provides power to the vehicle's electrical systems and charges the battery while the engine is running. It features a 145 Amp output, a 12 VDC system voltage, and a clockwise rotating 6-Groove serpentine pulley.
Show original supplier description
The ACDelco 20881337 is a GM Genuine Parts alternator, newly manufactured to be an exact replacement for your GM vehicle's original alternator. This alternator is built to rigorous General Motors standards, offering 145 Amps of output and operating at 12 VDC. It features a machined exterior and a 6-Groove serpentine pulley that rotates clockwise, ensuring compatibility with your vehicle's belt system. Some GM Genuine Parts may have formerly appeared as ACDelco GM Original Equipment (OE). GM Genuine Parts and ACDelco alternators are designed, engineered, and tested to support the high electrical loads of modern vehicles and help ensure durability and consistent performance. They are built to withstand a wide range of weather conditions. If your vehicle's alternator is failing, common signs include dashboard warning lights, flickering lights, a frequently dying battery, or starting issues. A failing alternator can also lead to permanent electrical damage to your battery and other components if not addressed promptly.

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

BrandACDelco
Part Number20881337
CategoryIgnitions and Electrical

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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