Trucks / GMC / Alternator / Sierra 5500HD
Used GMC Sierra 5500HD Alternator for Sale
- OEM used part
- Quality tested
- Fits 2019–2024
- Ready to ship
- 30-day warranty
- Core charge applies
A battery light on a GMC Sierra 5500HD is a countdown to a dead truck at the end of a route. We stock used OEM alternators for 2019–2024 GMC Sierra 5500HD trucks, load-tested and covered by our warranty, with the right pulley and connector for your engine. Send your VIN and engine and we confirm fitment before you pay.
How it works
This part is in our inventory and ready to ship. Share your VIN and we confirm fitment before you buy, then we’ll call you within about 30 seconds with your quote — or email it if we can’t reach you.
Signs your alternator has failed
- Battery or charging warning light on, or flickering at idle
- Headlights and dash dim at idle and brighten with RPM
- Batteries go dead overnight or after a short run — with new batteries
- Whine or growl from the alternator that changes with RPM
- Charging voltage under 13.2 V or over 15 V at idle
- Burnt smell, or a seized or wobbling pulley
Before you order
- Send your VIN and engine — output rating, mounting and connector change by engine and year; upfitted trucks may have a high-output option.
- Load-test the batteries and check cable ends and grounds first; a bad ground shows up as a charging fault.
- Inspect the belt and tensioner; a slipping belt kills output and the replacement’s bearings.
- On some trucks the ECM controls the alternator — verify the control circuit if a new unit won’t charge.
Other GMC Sierra 5500HD parts
Frequently asked questions
Do you sell used Alternator for all medium-duty truck brands?
Yes — we carry used alternator units for Isuzu, Ford, Chevrolet, GMC, Ram, and Mitsubishi Fuso medium-duty trucks, not just the GMC Sierra 5500HD.
Is this used Alternator tested before it ships?
Yes. Every alternator we sell is inspected and tested before it ships, so it works right the first time.
How do I order this Alternator?
Request a free quote above or call us. Share your VIN and we’ll confirm exact fitment, then call you back with a quote in about 30 seconds — if we can’t reach you, we’ll email it instead.
Do you offer a warranty on this Alternator?
Yes, we stand behind this alternator with our warranty. Exact terms are confirmed on your quote.
Do you ship this Alternator nationwide?
Yes — we ship to all 48 contiguous states with tracked delivery. Most parts arrive in 3–7 business days; engines, transmissions and axles ship freight and typically arrive in 5–10.
Do you test used alternators?
Yes — every alternator is bench-tested for output and diode ripple before it ships.
How do I know it’s the alternator and not the batteries or starter?
Charging voltage at idle tells the story: under 13.2 V with good batteries is the alternator; a slow crank with a full charge is the starter. Our charging-system guide walks through the 15-minute check.
Is there a core charge on this Alternator?
This alternator may carry a refundable core charge, returned when your old unit is sent back within 30 days. Any core charge is stated clearly on your quote.