Stone Exhaust Mercedes-Benz M274 C/X253 GLC250/300 Cat-Back Valvetronic Exhaust System
Unlock the sound and performance your Mercedes-Benz deserves with the Stone Exhaust Cat-Back Valvetronic Exhaust System for the M274-powered GLC-Class. This is the premium valved GLC exhaust upgrade for Mercedes GLC250 and GLC300 owners who want a deep, refined tone with zero drone, genuine performance benefits and OEM-level fitment. Precision 3D scanning, reverse engineering and in-house dyno development ensure exceptional results and an effortless install. If you are searching for Mercedes GLC250 exhaust, Mercedes GLC300 exhaust, GLC 250 4MATIC exhaust, GLC 300 4MATIC exhaust, C253 GLC Coupe exhaust, X253 GLC cat back, Valvetronic exhaust with remote or Mercedes M274 performance exhaust, this is the system to buy.
We run Stone on our own builds and our customers love the quality, the crisp Valvetronic control and the way it eliminates the drone found on the standard exhaust. Expect a true OEM-like fit, a sportier soundtrack on demand and calm cruising when you want it. Part Number: MP511S.
Why choose this GLC Cat-Back Valvetronic Exhaust
- Designed specifically for Mercedes-Benz M274 GLC-Class: X253 GLC250, X253 GLC300, X253 GLC300 4MATIC, C253 GLC 250 Coupe, C253 GLC 300 Coupe, C253 GLC 300 Coupe 4MATIC
- Premium Valvetronic GLC exhaust with dual valves for maximum control and everyday refinement
- Plug and play OBDII controller with remote for ON, OFF and AUTO modes
- Auto mode opens the valves at your chosen RPM for intelligent sound management
- One piece design, mechanical welding with precision and direct spot welding for strength
- Eliminates the drone found on the standard factory exhaust
- Rigorously developed using 3D scanning, reverse engineering and in-house dyno testing
- Engineered for a perfect OEM fit and easy installation
Valvetronic control. Daily comfort and track-ready sound
Stone’s independently developed Valvetronic system gives you complete control of volume and tone. Use the remote to select:
- ON for maximum sound and flow
- OFF for a quiet, refined drive
- AUTO to open and close the valves automatically at a preset RPM via the OBDII plug and play controller
The result is a Mercedes GLC valved exhaust that is loud when you want it and subtle when you do not.
Developed with real engineering
Stone engineers begin with full 3D scanning and reverse engineering of the OEM system to map pipe diameter, routing and bend angles. They then use 3D simulation to analyse exhaust gas flow, thermal zones and pressure rise, iterating until optimal performance is achieved. This delivers the precise fitment and consistent results you expect from a premium Mercedes-Benz GLC exhaust.
Built for accuracy and durability
- 7-axis CNC bending achieves 98 percent roundness and maintains only 25 percent outer bore wear at 180 degrees
- Integrally moulded exhaust pipe with accuracy error under 0.025 mm
- Crisscross and overlapping welding techniques increase weld penetration and endurance at high-temperature joints
- Direct spot welding by mechanical arms for superior precision and strength
OPF delete option included
Running an OPF-equipped Mercedes GLC? Stone supplies an OPF delete solution free of charge so you can install the Cat-Back without triggering error codes. No ECU coding is required to remove OPF errors.
Compatibility
M274 engine Mercedes-Benz GLC-Class
- X253 GLC 250 4MATIC (2015+)
- X253 GLC 300 (2015+)
- X253 GLC 300 4MATIC (2015+)
- C253 GLC 250 Coupe 4MATIC (2015+)
- C253 GLC 300 Coupe (2015+)
- C253 GLC 300 Coupe 4MATIC (2015+)
Part number
MP511S
Manufacturer and warranty
Manufactured by: Stone Exhaust
Warranty: Stone Exhaust 2 Year Warranty
Professional fitting
Want this Mercedes GLC Cat-Back Valvetronic Exhaust supplied and fitted by specialists? Nforcd offers professional installation at our Warwickshire facility. Request a fitting quote at Sales@nforcd.com.
Photos and videos
Fitted photos
Valvetronic system installation
Mercedes-Benz C253 GLC250 M274 x Stone Exhaust sound
Engineering gallery
Stone’s process includes full 3D scanning, 7-axis CNC bending and advanced welding for a precise, long-lasting result.
