Magnaflow · New
MagnaFlow Direct Fit Catalytic Converter 99-03 Lexus RX300 3.0L Rear
MPN 51318 · Store SKU mag51318
Supplier stock checked 11/7/2026, 5:45:40 AM UTC. Adding a part does not reserve it.
Request a return within 30 calendar days after delivery. New parts must be unopened and unused.
Shipping & returns ↗This policy does not limit rights required by law.Free standard shipping on eligible parts orders of $100 or more. Oversized and freight items excluded. Fitment, taxes, availability and final totals are confirmed before payment.
Product details
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Semi-Direct-Fit Catalytic Converter 51318. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this converter yourself using the proper tools, no welding required. MagnaFlow's state-of-the-art metrology department uses the latest 3D scanning systems during research and development, so you can be confident that your new part will fit and function like the original equipment. By replicating the OE design, the single laser fusion weld greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. This Direct-Fit Catalytic Converter is designed to fit the 1999-2003 Lexus RX300 3.0L & 2001-2003 Toyota Highlander 3.0L. MagnaFlow 51318 includes (1) Donut Gasket and interchanges with OE parts 17420-20130, 17420-20250, 17420-20290. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems. Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 51318. DIY installation is easy with the proper tools (no cutting or welding required). With features including mandrel-bent tubing to eliminate flow restrictions and stainless steel construction to resist corrosion, you can have confidence in the quality of this catalytic converter. Using state-of-the-art 3D scanning systems in the design process, the MagnaFlow metrology department ensures this new part to fit and function like the original equipment. Designed to fit the 1999-2003 Lexus RX300 and 2001-2003 Toyota Highlander, this direct-fit catalytic converter also interchanges with OE parts 17420-20130 and 17420-20250, among others. Avoid potential exhaust leaks by using the included gaskets to get a proper seal. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems. MagnaFlow OEM Grade Semi-Direct Fit Catalytic Converter Magnaflow OEM Grade Direct-Fit Catalytic Converter OEM Grade Semi-Direct Fit Catalytic Converter OEM Grade Direct-Fit Catalytic Converter
Manufacturer fitment & guides
Check 51318 against the manufacturer’s application information below.
Part-specific notes
- Not CARB approved. Destination and intended-use restrictions must be checked before sale.
- Emissions acknowledgement required before purchase.