Parts for your 2008 Mitsubishi Outlander-Exhaust gasket

2008 Mitsubishi Outlander exhaust gasket — what it does and when to replace it

Yes, the 2008 Mitsubishi Outlander uses exhaust gaskets. Technical sources including the Mitsubishi factory Service Manual for the CW series (2007–2013, Group 15 – Exhaust and relevant Engine sections) and the Mitsubishi ASA/parts catalogue for CW4W/CW5W/CW6W show multiple gaskets: a multi‑layer steel exhaust manifold gasket at the cylinder head, a crush “donut” gasket at the manifold/front pipe (spring‑bolt joint), and flat flange gaskets at mid and rear sections. These apply to both the 2.4L 4B12 and 3.0L 6B31 engines. So an exhaust gasket is very much a relevant part on this model.

The job of these gaskets is simple but critical: they seal hot exhaust gases so the Outlander runs quietly, keeps fumes out of the cabin, and lets the oxygen sensors read cleanly. A tight seal helps fuel trims stay steady, protects nearby components from heat and soot, and avoids that embarrassing tick or rasp on cold starts.

They’re not a set‑and‑forget wear item like brake pads, but they should be replaced whenever a joint is disturbed or any leak is suspected. The factory documentation specifies new gaskets on reassembly, particularly for the manifold and donut joints, and often calls for new spring bolts/nuts as well. Re‑using a crushed gasket usually ends in a comeback leak.

Tell‑tales that an Outlander exhaust gasket needs attention:

• Ticking, hissing, or chuffing noise that quietens as it warms up
• Sharp exhaust smell near the engine bay or under the floor
• Sooty marks around flanges or the manifold area
• Poor fuel economy or a check‑engine light linked to O2 sensor readings

Good servicing habits for this model:

• Inspect flanges, springs and donut seals at each major service or any time the exhaust is off the car
• Use new OEM‑spec gaskets, clean mating faces and check for warpage and corrosion
• Follow the workshop manual torque specs and fastener replacement notes for the manifold and spring‑bolt joints
• Support the exhaust properly when refitting to avoid stressing fresh gaskets
• If working near oxygen sensors, remove or protect them to avoid damage and reset trims if required

Done right, quality gaskets on a 2008 Outlander will stay leak‑free for years and kilometres, keeping the family wagon quiet, efficient and compliant.

FAQs

Does a 2008 Outlander have both a manifold gasket and a donut gasket?
Yes. The Mitsubishi service information and parts diagrams list a multi‑layer steel manifold gasket at the head and a crush‑type donut gasket where the front pipe meets the manifold via spring bolts, plus additional flange gaskets further back.

How can someone spot a leaking exhaust gasket on a 2008 Outlander?
Listen for a ticking or hissing on cold starts that fades as it heats up, sniff for exhaust odours near the engine bay or underbody, and look for black soot around joints. A scan tool may show fuel trim issues if the leak is ahead of the O2 sensors.

Can exhaust gaskets be re‑used on this model?
Best practice is no. The factory guidance expects new gaskets whenever a joint is opened, especially the donut and manifold gaskets, and recommends replacing spring bolts/nuts where specified to ensure proper clamping and a long‑lasting seal.