INTRODUCTION
Like all Acura products, the MDX benefits from an integrated approach to designing manufacturing quality into the original plan for the vehicle. This approach results in a vehicle that is sure to achieve the legendary durability, quality and reliability that is the hallmark of all Acura vehicles. To achieve the specified targets for quality, the MDX team had to carefully consider the logical assembly of components as well as the effects of time and wear on each part and system.
The development team conducted testing on three continents and covered thousands of miles of testing varying from bitter cold to sweltering heat, adding in variables of high and low altitude environments, with full loads and a battery of tests that left nothing to chance. These tests confirmed that MDX will perform at its impressive levels for years to come.
The following are a few of the many areas that show the attention to detail that typifies the design and engineering behind the MDX.
MINIMIZING NOISE, VIBRATION, HARSHNESS
A quiet interior is essential to any high quality vehicle. Towards that end, MDX engineers incorporated a host of design features and refinements aimed at blocking NVH from the passenger cabin. For 2004, several enhancements were made, including:
- Acoustic windshield glass
- Thinsulate added to the sideview mirrors
- Magnetic melt sheets
All powertrain-related hardware is double isolated from the main body structure by use of rubber mounting systems. A perimeter-type front subframe supports the engine, transaxle, steering, and front suspension lower control arms. Two engine mounts are hydraulic designs with internal damping, one of which is Electric Control Mounting (ECM) to provide excellent isolation throughout the broad range of excitation frequencies. An assortment of tuned-mass dampers attached to both the engine mounts and the subframe counteract resonance. A dual-path upper mount is used between each front spring and strut unit and the body structure.
The front axle half-shaft inner joints are designed with internal rollers that minimize friction. A two-piece tubular propeller shaft is used to transfer torque with no susceptibility to whip or vibration. A dynamic damper positioned inside the front tube is tuned to cancel out vibration at cylinder-firing frequencies. The rear drive unit is supported by three rubber mounts in a second subframe, which is in turn attached to the body structure through four widely spaced rubber mounts. Rear coil springs are insulated from both the body and the rear suspension hardware by means of upper and lower rubber pads.
Various fuel tank subsystems - the fuel vapor canister, the assembly, and the ABS modulator - are rubber isolated from the body to block any sympathetic NVH contribution.
The engine's high volume intake and exhaust systems are engineered for non-restrictive but quiet flow through the engine. Just aft of the point where left- and right-bank exhaust flow join, a corrugated flex pipe is positioned to permit quiet movement between the engine and the remainder of the exhaust system. A large pre-chamber muffler near the middle of the vehicle is glass-filled to absorb high-frequency exhaust noise. The high-volume silencer near the rear bumper has dual outlets to ensure exhaust flow requirements are met during full throttle acceleration.
Extensive sound deadening is used within MDX's body structure. For 2004, magnetic melt sheets replace those made of asphalt and reinforcement material used on previous MDX models to improve isolation from road noise and reduce overall weight of the vehicle. The melt sheets - whose particles bond to surfaces in the paint ovens - cover virtually the entire floor of the vehicle from the vertical dash panel to the liftgate sill. An acoustic roof lining runs from front to rear while additional sound-deadening material blankets the dash panel and the rear of the hood. Molded rear fender liners help quiet road splash and tire noise. Another new feature of the 2004 MDX is the application of acoustic windshield glass to reduce cabin noise. To create a noise barrier at the base of the A, B, and C pillars, expanded foam fills these cavities. This foam is expanded by the heat of the paint-curing ovens, noise from the floor area is blocked from being transmitted inside the pillar cavities to the interior compartment.
Special recycled textile absorption blankets are attached to the underside of the instrument panel and the sides of the center console.
Design of the door mirrors is especially sensitive to wind noise. The MDX features diffuser side mirrors that smoothly channel air between the mirrors and the window glass for reduced wind noise. A layer of Thinsulate™ has been added to the side mirrors to further reduce wind noise. Sponge material between the base and the door surface eliminates the possibility of gaps in that area. The molding to base interface is also a zero-gap design.
Additional weatherstrips are positioned in critical window frame to pillar gaps to help maintain smooth air flow down the side of the vehicle.
The bottom line is a net lack of road, powertrain, and wind noise inside the passenger compartment. In competitive tests, MDX compares favorably with the best luxury-class SUVs in overall NVH performance.
QUALITY CRAFTSMANSHIP, QUIET INTERIOR
The MDX is the first sport utility vehicle designed with a no compromise engineering philosophy. MDX delivers fresh styling, unmatched versatility, car-like driving exhilaration, class-leading safety and environmental responsibility while also upholding Acura's well established reputation for outstanding value. Acura customers expect best in class quality. Towards this end, MDX has the refined attention to detail lacking in several of its luxury SUV class competitors.
Body gaps are best in class by an impressive margin. Exterior design is clean, functional, and well proportioned. Adornments are elegant and tasteful. Door jams are neatly finished. MDX sets a new standard for quality craftsmanship in its class.
DOOR HANDLES
MDX's pull-type door handles are chrome plated for a luxury look and feel. Clearance pockets behind each release handle are generously sized to provide room for gloved hands and to avoid ring and fingernail scratches.
TIGHT, CONSISTENT PANEL GAPS
To minimize construction tolerances, MDX's doors are attached to the car by rigid bolts that pass through zero-clearance hinge holes. Doors are made of high-strength, galvanized steel for dent resistance. Front mud guards are provided to deflect rocks and debris and rear splash guards are standard accessories. Lower door surfaces are painted with a soft primer that is especially resistant to stone chips. Seals that extend from the lower edges of the doors to the sill area block the build up of dirt and debris that might otherwise soil clothes during entry and exit from the vehicle.
Most MDX gaps are between 0.12- and 0.18-inch. To permit a tighter fit between rear quarter window and the adjacent quarter panel, a beveled edge is used on the glass.
Seals and covers are positioned in door jams and sill areas to mask assembly welds. In the liftgate opening, the trim has a clean appearance that's not marred by the visible bumper clips used by some competitors. All interior trim is retained with hidden fasteners. Front and rear wipers are smooth, single-piece designs for a clean look.
Door mirrors have blue-tinted glass to cut glare at night. Electrical heating grids can be activated by a switch near the remote mirror control pad to clear frost and fog from the mirror surface.
Side and rear window glass is deeply tinted for privacy and to keep the interior cooler during summer months.
MANUFACTURING
The MDX is built at Honda of Canada Manufacturing in Alliston, Ontario, near Toronto.