The Walker Exhaust 55183 Exhaust Muffler Assembly is engineered to provide a direct-fit, OE-style replacement for the 1998-2000 Toyota Sienna, ensuring seamless integration and optimal performance. Constructed with 100% stainless steel, this muffler offers superior corrosion resistance compared to traditional aluminized mufflers, extending its service life and reducing maintenance costs. The internal drainage system effectively minimizes moisture accumulation, further enhancing durability. Designed with internal partitions and mechanically joined tubes, the muffler accommodates thermal expansion and contraction, reducing distortion and maintaining structural integrity over time. Spun-locked heads and OE-style spot welds contribute to its robust construction, ensuring long-term reliability. Acoustic and flow testing validate its design, delivering a factory-style sound quality that meets OE standards. The muffler's dimensions—59.125 inches in overall length, 11 inches in body width, and 5.5 inches in body height—are tailored to fit the specified vehicle models precisely. With an inlet and outlet diameter of 2.25 inches, it facilitates efficient exhaust flow, supporting engine performance. The muffler's oval shape and aluminized finish not only enhance its aesthetic appeal but also provide additional protection against environmental factors. This product is backed by Walker's limited lifetime warranty and exclusive 90-Day Safe and Sound® Guarantee, offering peace of mind and assurance of its quality and performance.