High-Torque Starter Motor for Chevrolet Avalanche, Isuzu Ascender, Buick Rainier & GMC Envoy (OE PN6494)

A High-Torque Starter for the Envoy, Rainier & Avalanche

This is a high-torque starter motor built for the 2007-2008 Chevrolet Avalanche, 2004-2006 Isuzu Ascender, 2004-2007 Buick Rainier, and 2005-2009 GMC Envoy, cross-referenced to OE number PN6494 and replacing OEM numbers including 6494N, 12568051, and 89-01-7440. If your SUV or truck is cranking slowly, clicking without starting, or completely silent when you turn the key, a worn starter motor is one of the most common causes across this shared GM platform.

Why One Starter Fits Four Different Nameplates

The Avalanche, Ascender, Rainier, and Envoy from these model years share closely related GM platform architecture and engine mounting points, even though they were sold under four different brand names spanning Chevrolet, Isuzu, Buick, and GMC. Because a starter motor's mounting bolt pattern and flywheel engagement are tied to the shared engine and bellhousing design rather than to the badge on the grille, the same starter fits all four vehicles wherever that platform and engine combination was used.

Key Features

• Cross-referenced to OE number PN6494 and multiple superseded part numbers
• Rated 1100W with 174A max current for reliable high-torque starts
• IP54 protection rating guards against dust and moisture
• 9-tooth, clockwise-rotation design for direct-fit installation

Specifications

• Voltage: DC 12V
• Rated power: 1100W
• Max current: 174A
• Gear teeth: 9T, clockwise rotation
• Condition: New

Compatibility

Fits the 2007-2008 Chevrolet Avalanche, 2004-2006 Isuzu Ascender, 2004-2007 Buick Rainier, and 2005-2009 GMC Envoy. Because these vehicles were built across multiple model years with different engine and drivetrain options, it's worth confirming your specific vehicle and engine against the OE number above before ordering.

Signs Your Starter Motor Needs Replacing

A failing starter typically announces itself with a single click and no engine turnover, a slow or labored cranking sound, grinding noise as the starter gear engages the flywheel, or complete silence when you turn the key despite the dashboard lights working normally. Because a starter issue can sometimes be confused with a weak battery, having your battery tested first will help confirm the starter itself is the actual cause before you replace it, since a marginal battery can mimic several of the same symptoms.

Why a High-Torque Starter Matters

A high-output engine or one with higher compression needs more rotational force to turn over reliably, especially in cold weather when oil is thicker and resistance is higher. Because this starter is rated for 1100W with 174A of max current, it's built to deliver the torque these SUVs and trucks need for consistent starts across a range of temperatures and conditions, rather than just barely meeting the minimum requirement, which matters most on cold mornings when the engine needs the most help turning over.

Installation Notes

Replacing this starter means disconnecting the battery, locating the starter on the engine block or bellhousing, disconnecting its electrical connections, removing its mounting bolts, and installing the new unit in reverse order. Because the starter's electrical connections carry significant current, making sure the battery is fully disconnected before starting the job and double-checking all connections are tight and clean during reassembly will help ensure a reliable start every time, especially in cold weather when a loose connection is more likely to cause a no-start.

Ordering Information

This starter motor is in stock and ships ready to install. Our Shipping Information page covers current timelines, and our Warranty and Returns pages explain what to do if anything isn't right on arrival. Not sure this matches your specific vehicle and engine? Our Request a Part page is the fastest way to confirm before you order.

Related Parts

This starter motor is listed in our Starters collection, along with our Chevrolet and GMC collections, where you'll find other components for these platforms.