DIY Muffler Cover: Eliminate the Grass Fire Danger
This DIY video shows how to fabricate and install a muffler cover/heat shield to stop a hot muffler from igniting tall grass and debris under a parked vehicle. The build uses a small sheet of metal, mounting hardware, and simple tools to create a protective guard that directs heat away from vegetation and provides physical protection for the muffler.
Build Sequence
1. Inspect muffler area and measure
Park the vehicle on level ground, allow the exhaust to cool completely, and inspect the muffler, surrounding clearances, and any nearby heat-sensitive materials. Measure the muffler circumference, length of the area to be covered, and distance to chassis mounts to determine shield dimensions and mounting points.
2. Design template and mark metal
Lay out a paper or cardboard template to verify fit, then transfer the shape to the stainless steel sheet. Mark bend lines, attachment holes, and cut lines. Consider adding flanges for rigidity and attachment locations for straps or brackets.
3. Cut and shape the shield
Cut the sheet metal to shape using an angle grinder, jigsaw, or nibbler. Trim to fit and create any required bends using a vise, hammer over a form, or metal brake. Smooth edges with a file or deburring tool to prevent cuts or rubbing on hoses.
4. Attach brackets/straps and prepare mounting
Drill holes for rivets or bolts and attach mounting straps or brackets to the shield. If using hose clamps, fit the clamps to the shield and ensure there's a secure seating area. Add reflective tape where desired for extra heat rejection.
5. Mount shield and verify clearances
Fit the shield over the muffler and secure with clamps, riveted brackets, or bolts to chassis mounting points. Ensure there is adequate clearance from suspension components, wiring, and the body—aim for a small air gap between shield and muffler. Recheck exhaust movement under load (if possible) and retighten fasteners.
6. Final inspection and test
Inspect all fasteners, ensure there are no sharp edges, and verify the shield won’t contact any components during wheel travel or body movement. Take a short test drive and re-inspect mounts for looseness or chafing. Adjust as necessary.
Frequently Asked Questions
What material is best for a muffler cover?
Stainless steel is preferred for durability and corrosion resistance at exhaust temperatures. Aluminum or aluminized steel can work but may not last as long near road salts or in high-heat conditions.
VIEW FULL ARTICLE →Can I weld the shield instead of riveting or clamping?
Yes — welding offers a permanent attachment if you have the skill and equipment. However, welding on or near exhaust components requires care and knowledge of heat effects; rivets or bolts are easier and safer for most DIYers.
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Parts Used (5)
Cut and formed into a muffler cover or heat shield; stainless resists corrosion and high heat.
Optional layer to improve heat rejection where the shield faces the muffler.
Used to clamp the shield to the muffler or exhaust pipe when brackets aren't practical.
Provides solid attachment points to hang or secure the cover to the exhaust or chassis.
Fastens shield pieces together and attaches brackets when welding isn't used.