ISR Performance MBSE Dual Axle-Back Exhaust for the Lexus IS 250, IS 300, and IS 350 RWD
The factory exhaust on the third-generation Lexus IS is built for refinement, not character. The ISR Performance MBSE Dual Axle-Back replaces the rear muffler section with twin polished mufflers, dual 2.5-inch piping, and rolled tips that give the IS the aggressive tone its sport-tuned chassis deserves, all while keeping installation simple.
What It Is
The ISR Performance MBSE Dual Exhaust is an axle-back exhaust system for the 2013-2020 Lexus IS RWD platform. It replaces the factory rear muffler section with twin mandrel-bent stainless steel mufflers, dual 2.5-inch piping, and polished rolled tips. As an axle-back system, it bolts directly to the existing factory mid-pipe, which keeps the install simple and avoids touching the cats or any emissions hardware.
What It Does
The factory rear muffler section on the Lexus IS is heavy, restrictive, and tuned for maximum quietness. The ISR MBSE Dual replaces it with a freer-flowing dual 2.5-inch design that improves exhaust flow through the rear of the system and unlocks a deeper, more aggressive tone. The polished mufflers and rolled tips also give the rear of the car a significantly more sport-oriented visual presence than the factory single-tip layout on most IS trims.
Since this is an axle-back system, you're not making major peak power gains. The performance benefit is improved exhaust flow at the back of the system and a more engaging exhaust note. The visual and aural upgrade is the primary reason most buyers choose this style of exhaust.
Construction Quality
The MBSE Dual is built from mandrel-bent stainless steel with precision TIG welds throughout. Mandrel bending preserves consistent pipe diameter through curves, which keeps exhaust flow smooth instead of restricting it the way crush-bent piping does. The piping is brushed stainless and the mufflers are polished, giving you a clean two-tone look that holds up better than chrome-plated alternatives over time.
Fitment and Compatibility
This exhaust fits the 2013-2020 Lexus IS in the following configurations:
- Lexus IS 250 RWD
- Lexus IS 300 RWD
- Lexus IS 350 RWD
Critical fitment note: This system is for rear-wheel drive models only. It will NOT fit AWD variants of the Lexus IS. AWD models use a different rear chassis and exhaust routing that this system isn't designed to clear. Verify your model is RWD before purchasing.
Who This Is For
This exhaust fits a few common build profiles. If you own a 2013-2020 Lexus IS RWD and the factory exhaust note doesn't match how the car feels to drive, this is the fix. If you want a complete-looking dual-tip exhaust without paying for a full cat-back system, the axle-back design delivers most of the visual and audio change at a lower price point. If you want a quality stainless system that won't rust out within a few years like cheap aftermarket options, the mandrel-bent stainless construction holds up.
What's in the Box
- 2x Rear muffler sections
- 4x Bolts
- 4x Nuts
Installation Notes
Axle-back exhaust installation is one of the easier exhaust jobs you can do. The system bolts directly to the factory mid-pipe at the existing flange connection. The vehicle needs to be lifted to access the rear muffler section, and the factory rear section is unbolted and removed before the ISR sections are installed in its place. All necessary hardware is included. Professional installation is recommended if you don't have access to a lift, but the swap is well within reach for any home garage with jack stands.
Off-Road and Competition Use
This exhaust is legal only for use in competition vehicles which may never be registered, licensed, or used on public streets or highways, and for use in other exempted vehicles. It is not 50-state street legal. Verify local emissions and noise regulations before purchasing if you intend to drive the vehicle on public roads.
Product Details
Brand: ISR Performance
Product: MBSE Dual Axle-Back Exhaust
Vehicle Fitment: 2013-2020 Lexus IS 250, IS 300, IS 350 (RWD only)
Drivetrain Compatibility: Rear-wheel drive only (NOT compatible with AWD)
Type: Axle-back
Material: Mandrel-bent stainless steel
Construction: Precision TIG welded
Piping: Brushed stainless, dual 2.5 inch
Mufflers: Polished, twin
Tip Style: Polished rolled
Legality: Off-road and competition use only, not 50-state street legal
Key Benefits: Deeper, more aggressive tone, dual-tip rear visual upgrade, improved rear-section flow, mandrel-bent stainless durability