Chrysler's Multi-Displacement System (MDS) is an automobile engine variable displacement technology. It debuted in 2004 on the 5.7 L modern Hemi V8. Like Mercedes-Benz's Active Cylinder Control, General Motors' Active Fuel Management, and Honda's Variable Cylinder Management, it deactivates four of the V8's cylinders when the throttle is closed.
The system was first offered only on passenger cars, since the heavy demands of trucks would interfere with its operation. However, it was recalibrated for 2006 and will be offered on all seven models, including SUV's and 1500 series trucks, using the 5.7 L engine.
Chrysler expects that the technology will boost economy by 10% to 20%. In the Jeep Grand Cherokee with MDS, highway fuel mileage for the V8 is the same as the V6 at 21 mpg (11.2 liters per 100 km).
In order to preserve the characteristic rumble of the V8 engines, Chrysler and Eberspaecher North America designed a special exhaust system for MDS-equipped vehicles. This includes four separate mufflers, two large central ones for V8 mode and two smaller ones near the tailpipes for straight-4 operation. Unlike the system used on Mercedes-Benz V12 engines, also designed by Eberspaecher, the system is mechanically passive.
- 2005- Chrysler 300C
- 2005- Dodge Charger
- 2005- Dodge Magnum
- 2009- Dodge Challenger
- 2005- Jeep Grand Cherokee
- 2007- Chrysler Aspen
- 2006- Dodge Durango
- 2006- Dodge Ram (1500 only)
- 2006- Jeep Commander
- Variable displacement
- Honda's Variable Cylinder Management (VCM)
- General Motors' Active Fuel Management (AFM)
- Daimler AG's Active Cylinder Control (ACC)