Quiet your exhaust and keep spent gases flowing with the AP EXHAUST muffler assembly (P/N 40021). It installs as a direct-fit replacement for the 2006 HUMMER H3 [L5-3.5L] and the 2007-2010 HUMMER H3 [L5-3.7L], ready to swap in for a rusted-out or blown factory muffler.
A muffler dampens the pressure pulses of the exhaust stream to reduce noise while allowing gases to pass through. Signs the original may need replacing include a louder or droning exhaust note, a rattle from a broken internal baffle, or visible rust-through and perforation on the shell. If a failed muffler is the source of your noise, this assembly replaces it. Sold as a single unit; one is used per listed application.
What vehicles does the AP EXHAUST muffler assembly 40021 fit?
It fits the 2006 HUMMER H3 with the L5-3.5L engine and the 2007-2010 HUMMER H3 with the L5-3.7L engine. See the Buyer's Guide tab to confirm your vehicle.
What is this muffler made of?
The muffler is made of aluminized steel, which resists corrosion from road salt, moisture, and hot exhaust gases.
Where is this muffler assembly made?
Its country of origin is the United States.
How many mufflers do I need for my H3?
The listed applications use one muffler per vehicle, and this listing is for a single assembly.
How do I know my muffler needs replacing?
Common signs include a louder or droning exhaust, a rattle from a broken internal baffle, or visible rust-through on the shell. Diagnose the cause before replacing.
WARNING: These products can expose you to chemicals including lead and phthalates, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
