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Internal Muffler Insert - Available 5in, 6in, 7in & 8in

Internal Muffler Insert - Available 5”, 6” 7” & 8”. This quiet series muffler has bee designed to reduce the exhaust noise component of heavy duty trucks to allow compliance with noise limits set by paragraph 27204 of the California Vehicle code. The acoustical insertion loss of the internal muffler is compared to that of an OEM muffler.

This Muffler Insert will reduce the exhaust noise level to equal that of an OEM muffler. Additionally, this muffler exhibits a 1.55 inch Water Column pressure drop compared to 8.4 inch WC pressure drop of the same OEM muffler at 1000 CFM airflow at 70 degree F.

4 State Trucks

4579 Highway 43
Joplin, MO 64804

Toll Free: 888-875-7787
Local: 417-624-3054
Fax: 417-624-2489

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