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Steering and Turning Diameter
The Pilot�s rack-and-pinion steering system is tuned for quick, linear, car-like response and sensitive feel � and the torque-sensing power steering assist is high for parking maneuvers and low at highway speeds. For towing, standard equipment includes a heavy-duty power steering fluid cooler. The system uses heat-resistant rubber mount bushings, high-pressure die cast aluminum gear housings, a low friction material rack guide for good on-center feel and a damper valve to reduce steering wheel vibration. The Pilot features a tight turning diameter of 38.6 feet for excellent low-speed maneuverability.
Wheels and Tires
A 65-series tire was selected to provide optimum comfort for all passengers. Tires are P245/65/R17 105T radials mounted on 17 x 7.5-inch wheels. The Pilot LX is equipped with styled steel wheels, while Pilot EX, EX-L and Touring models feature cast alloy wheels with a bright machined look. The Pilot Touring has an exclusive wheel design for a more upscale appearance. Seventeen and 18-inch chrome finish alloy wheels are available as a dealer-installed accessory on all models.
The compact spare is carried under the rear load floor and can be lowered by turning a hidden hex-head bolt with the provided lug-nut wrench. The hex-head bolt is located under a cover conveniently located in the rear hatch trim area. This arrangement guarantees the security of the spare and keeps it readily accessible without disturbing luggage or cargo carried onboard. Room is provided to stow a flat or a full-size spare in the compact spare's location.
Braking System
Consistent with its use as a people and cargo hauler and as a towing platform, the 4-wheel disc brakes on the 2009 Pilot are the largest brake system ever featured on a production Honda vehicle. The brake system is engineered to provide high levels of braking capability. The ventilated front brake rotors are 13.0-inches in diameter with a thickness of 1.1-inches, while the solid rear rotors are 13.1-inch diameter units with a thickness of 0.43-inches. Dual-piston cast iron brake calipers are used in front and single-piston cast iron calipers are fit in back. A single stage vacuum booster consists of one 10.5-inch diameter booster chamber.
The Pilot features large capacity brake components. Consisting of four-wheel disc brakes and four-channel anti-lock brakes, the Pilot�s brakes are tuned for stable and linear braking forces. For optimum performance with widely varying loads, Pilot has Electronic Brake Distribution system (EBD) technology. EBD monitors braking force and adjusts front-to-rear brake effort to achieve maximum braking performance and stability. At the rear, a select-low braking strategy is used to help maintain directional stability in slippery driving. In the event one rear wheel verges on lock-up, triggering a pressure modulation at that wheel, brake pressure is also diminished at the adjoining wheel to help preserve the rear axle's lateral stability. The parking brake is set by stepping on a pedal located on the left side of the driver�s foot well, freeing space in the center console area. The release is located on the lower left side of the instrument panel.
Anti-Lock Braking System (ABS) with Electronic Brake Distribution (EBD) and Brake Assist
The Pilot�s Anti-Lock Braking system (ABS) has four sensing and activating channels to detect a wheel on the verge of lock up. In the event this occurs, brake pressure is held and then reduced to permit that wheel to regain traction before full braking resumes. The front suspension geometry has a very small scrub radius to help maintain dynamic stability even when one front wheel is braking harder than the other because of uneven traction conditions. (See the safety section for more information.)
Vehicle Stability Assist with Traction Control
Vehicle Stability Assist� (VSA�), also known as electronic stability control, is included as standard equipment. By continually monitoring the vehicle�s operating parameters (such as road speed, throttle position, steering wheel position along with acceleration, braking and cornering loads), VSA anticipates the vehicle approaching oversteer or understeer. To help correct either of these situations, VSA first acts to transfer torque bias to the axle with the most traction. This preventative measure significantly reduces the number of brake and throttle interventions. The response is so quick that the instability may be corrected even before the driver knows it is occurring. Traction Control is integrated into the VSA, and it helps the vehicle accelerate smoothly on slippery surfaces. (See the safety section for more information.)
Off-Road Capability
Honda took thorough measures to ensure that people with medium duty off-road needs would be satisfied with the Pilot. The vehicle meets design criteria, which was based on research at different off-road areas across the country.
This research was the foundation for specific minimum performance criteria for the new Pilot, including travel through standing water nearly 19-inches deep, off-road friendly approach and departure angles (27.8 degrees front and 24.5 degrees rear, respectively), rocks, off road and paved grades up to 60 degrees. Components located underneath the vehicle are tucked away to avoid damage in off-highway driving and the fuel tank�s evaporative canister is protected by a high-strength steel guard.
The available VTM-4 system with computer-controlled traction capabilities helps the Pilot meet typical off-road challenges without the need for low-range gears. (See powertrain section for full description.) The system is designed for �decision free� operation meaning that the driver does not need to actively choose when to engage four-wheel-drive. The system is always active and ready to proportion rear wheel torque as needed. For stuck situations in mud or snow, a driver-selected 4WD �lock� mode locks the two rear wheels together at speeds up to 18mph. Consistent with typical SUVs, the front approach, break-over and rear departure angles enable the Pilot to meet the medium duty off road needs of its target buyers.
Hill Start Assist
New for 2009, Hill Start Assist helps to prevent the vehicle from rolling backwards when the driver switches from the brake pedal to the accelerator pedal while the vehicle is stopped on a hill. Hill Start Assist automatically activates when the road incline exceeds a 10 degree threshold and the vehicle is fully stopped in any forward or reverse gear. The system uses a longitudinal G-sensor along with a wheel speed sensor and steering angle sensor to control the hydraulic brake modulator. While activated, the brakes are released when the driver depresses the throttle to make the vehicle move.
Tire Pressure Monitoring System
An onboard Tire Pressure Monitoring System (TPMS) warns the driver if the air pressure decreases significantly in any tire. The system helps reduce the chance of damaging a tire or losing control of the vehicle due to low air pressure. This is important because a slow leak, such as one that might be caused by a nail or road debris, might not be easily detectable but could cause loss of grip and potentially a blowout.
TPMS uses a sensor mounted on each wheel that continually monitors tire pressure and sends a coded signal to the TPMS electronic control unit (ECU). The process begins with a signal initiator located inboard of each tire on the chassis. The initiator sends a unique signal for each TPMS sensor. Then the TPMS sensor sends tire pressure data to the TPMS ECU, which compares the values for each tire�s pressure against an acceptable range of pressures. When a tire�s pressure drops significantly below the proper level, an alert will appear on the information display screen.
On the Pilot Touring model, the system can display the air pressure in all four tires simultaneously via the Multi-Information Display (MID). At the driver�s preference, the MID can continually show the air pressure in all four tires. Regardless of whether the driver chooses to monitor the pressures, a warning will still occur if a tire drops significantly below specification.
Fuel System
The 21.0gallon, saddle-shaped fuel tank is molded of high-density polyethylene for low weight, freedom from corrosion and impact resistance. It is positioned ahead of the rear wheels and over the propeller shaft to help guard against collision damage. The shape of the tank is designed to diminish the likelihood of sloshing-fuel noise. The polyethylene filler pipe and fuel lines are lightweight, and resistant to corrosion and fuel vapor losses. A high-efficiency fuel pump is housed inside the fuel tank. The fuel-filter is a lifetime design that never needs replacement.
2009 Honda Pilot: Powertrain
The Honda Pilot is designed to provide a comfortable, confident and fun driving experience with plenty of power to match its capabilities as an eight-passenger SUV with off-road capabilities and up to 4,500-pound towing capabilities (4WD). For 2009, Honda engineers prioritized fuel efficiency for the all-new Pilot and applied the latest generation of the company�s Variable Cylinder Management technology to all models. Low emissions, a broad torque curve and low maintenance were also key development targets.
The Pilot is powered by an advanced 3.5-liter 24-valve i-VTEC, V-6 engine mated to an electronically-controlled 5-speed automatic transmission. Peak engine output is 250 horsepower at 5700 rpm and 253 lb-ft. of torque at 4800 rpm. The �intelligent� Variable Valve Timing and Lift Electronic Control (i-VTEC�) valvetrain technology with Variable Cylinder Management (VCM) allows the V-6 engine to operate in six-cylinder mode for power and four- and three-cylinder modes for efficiency. The Pilot meets California�s stringent Ultra Low Emissions Vehicle (ULEV-2) exhaust emissions standards. A fully-automatic Variable Torque Management 4-wheel drive system (VTM-4) is available on all models and delivers seamless �decision free� application of four-wheel drive when needed.
Powertrain Summary
- 3.5-liter i-VTEC engine
- 250 horsepower at 5700 rpm, 253 lb-ft. of torque at 4800 rpm
- Variable Cylinder Management
- Honda-estimated EPA city/highway fuel economy(1) of 17/23 (2WD) and 16/22 (4WD)
- ULEV-2 emissions rating (CARB)
- VTM-4 four-wheel drive (available)
- 100K +/- Miles No Scheduled Tune-Ups(2)
- Regular unleaded gasoline
(1) Based on 2009 EPA mileage estimates, reflecting new EPA fuel economy methods beginning with 2008 models. Use for comparison purposes only. Do not compare to models before 2008. Actual mileage will vary.
(2) Based on 2009 EPA mileage estimates, reflecting new EPA fuel economy methods beginning with 2008 models. Use for comparison purposes only. Do not compare to models before 2008. Actual mileage will vary.
Powertrain Specifications: 2009 Pilot vs. 2008 Pilot
| 2009 Pilot | 2008 Pilot | Change from 2008 | |
| Engine Size (L) | 3.5 | 3.5 | Same |
| Engine Output (HP) | 250 @ 5700 | 244 @ 5750 | +6 @ -50 rpm |
| Engine Output (lb-ft.) | 253 @ 4800 | 240 @ 4500 | +13 @ +300 rpm |
| Valvetrain (4WD) | i-VTEC w/ VCM | VTEC | Added VCM |
| Valvetrain (2WD) | i-VTEC w/VCM | i-VTEC w/VCM (6/3) | Added 4cyl mode |
| Compression Ratio | 10.5:1 | 10.0:1 | +0.5:1 |
| Fuel Economy* (mpg city/hwy) | 17/23 (2WD) 16/22 (4WD) | 16/22 (2WD) 15/20 (4WD) | +1/+1 +1/+2 |
| Emissions (CARB) | ULEV-2 | ULEV-2 | Same |
| 4WD (Available) | VTM-4 | VTM-4 | Same |
| 100K +/- Miles No Scheduled Tune-Ups | Standard | Standard | Same |
| Tow Rating 2WD/4WD | 3500 / 4500 | 3500 / 3500** | Same / +1,000** |
* Based on 2009 EPA mileage estimates, reflecting new EPA fuel economy methods beginning with 2008 models. Use for comparison purposes only. Do not compare to models before 2008. Actual mileage will vary. ** Applies to box trailer tow rating or boat towing. On 2003-2008 4WD models, a tow rating of 4,500 pounds for boats only was possible when properly equipped.
Key New Features
- Variable Cylinder Management with switching between 6-, 4- and 3-cylinder modes
- Cold air intake
- Magnesium intake manifold (4WD only)
- Active Control Engine Mount (ACM) and Active Noise Control (ANC) on 4WD models
Engine Architecture
The Pilot�s engine is an advanced 3.5-liter, SOHC, 24-valve, 60-degree, V-6, aluminum-block-and-head design that is compact, lightweight and powerful. The i-VTEC valvetrain and high efficiency intake manifold optimize cylinder-filling efficiency across a wide range of engine speeds. Low-restriction intake and exhaust systems, a 10.5:1 compression ratio and roller-type rocker arms further aid efficiency and power delivery across a broad rpm range.
Engine Block
The Pilot has a die-cast lightweight aluminum alloy block with cast-in-place iron cylinder liners. Made with a centrifugal spin casting process, the thin-wall liners are high in strength and low in porosity. The block incorporates a deep-skirt design with four bolts per bearing cap for rigid crankshaft support and minimized noise and vibration. Both the block and caps are heat treated for greater strength.
Crankshaft, Connecting Rods and Pistons
A forged steel crankshaft is used for maximum strength, rigidity and durability with minimum weight. Instead of heavier nuts and bolts, connecting rod caps are secured in place with smaller, high-tensile-strength fasteners that screw directly into the connecting rod. Short-skirt, cast-aluminum, flat-top pistons are notched for valve clearance and fitted with full-floating piston pins.
Cylinder Head
Like other Honda V-6 powerplants, the Pilot V-6 cylinder heads are a SOHC design, with the cams driven by the crankshaft via an automatically tensioned toothed belt. Made of low-pressure cast, low-porosity aluminum, each cylinder head incorporates an integrated exhaust manifold to reduce parts count, improve flow and optimize the location of the close-coupled catalyst on each cylinder bank.
The cylinder head employs four-valve combustion chambers, the best approach to optimum performance with excellent fuel efficiency and very low emissions. Valves are clustered near the center of the bore to minimize combustion chamber volume and to provide ample squish area. A 10.5:1 compression ratio helps maximize thermal efficiency, power output and fuel efficiency. One centrally located camshaft per cylinder bank is driven by a fiberglass-reinforced toothed belt. Head gaskets are made of high-strength materials to contain combustion pressures.
Dual-Stage Intake Manifold
The Pilot uses a dual-stage intake manifold that is designed to deliver excellent airflow to the cylinders across the full range of engine operating speeds. On four-wheel-drive models, the two-piece manifold is extremely light due to its cast magnesium design. The intake manifold on two-wheel-drive Pilot models is constructed of aluminum using an identical design.
The induction system significantly boosts torque across the engine's full operating range. Internal passages and two butterfly valves within the intake manifold are operated by the powertrain control module to provide two distinct modes of operation by changing plenum volume and intake airflow routing.
At lower rpm these valves are closed to reduce the volume of the plenum and effectively increase the length of inlet passages for maximum resonance effect and to amplify pressure waves within each half of the intake manifold at lower rpm ranges. The amplified pressure waves significantly increase cylinder filling and torque production throughout the lower part of the engine�s rpm band.
As the benefits of the resonance effect lessen with rising engine speed, the butterfly valves open at 4200 rpm to interconnect the two halves of the plenum, increasing its overall volume. An electric motor, commanded by the powertrain control module, controls the butterfly valves. The inertia of the mass of air rushing down each intake passage helps draw in more charge than each cylinder would normally ingest. The inertia effect greatly enhances cylinder filling and the torque produced by the engine at higher rpm.
i-VTEC with 3-stage Variable Cylinder Management� (VCM�)
To help improve the fuel efficiency of the V-6 engine, the latest generation of Honda�s VCM is used (similar to the Accord V-6). This is the first application of VCM on a Honda 4-wheel-drive model. (The previous generation of VCM used in the 2007 - 2008 Pilot switched between three- and six-cylinder operation and was used exclusively in two-wheel-drive models.) The Pilot�s new VCM system can operate on three, four or all six cylinders, and is standard on all both two-wheel-drive and four-wheel-drive models.
During startup, acceleration or when climbing hills � any time high power output is required � the engine operates on all six cylinders. During moderate speed cruising and at low engine loads, the system operates just one bank of three cylinders. For moderate acceleration, higher-speed cruising and mild hills, the engine operates on four cylinders.
With three operating modes, the VCM system can finely tailor the working displacement of the engine to match the driving requirements from moment to moment. Since the system automatically closes both the intake and exhaust valves of the cylinders that are not used, pumping losses associated with intake and exhaust are eliminated and fuel economy increases. The VCM system combines maximum performance and maximum fuel economy � two characteristics that do not typically coexist in conventional engines.
VCM deactivates specific cylinders by using the VTEC (Variable Valve-Timing and Lift Electronic Control) system to close the intake and exhaust valves while simultaneously the Powertrain Control Module cuts fuel to those cylinders. When operating on three cylinders, the rear cylinder bank is shut down. When running on four cylinders, the left and center cylinders of the front bank operate, and the right and center cylinders of the rear bank operate.
The spark plugs continue to fire in inactive cylinders to minimize plug temperature loss and prevent fouling induced from incomplete combustion during cylinder re-activation.
The system is electronically controlled, and uses special integrated spool valves that do double duty as rocker-shaft holders in the cylinder heads. Based on commands from the system�s electronic control unit, the spool valves selectively direct oil pressure to the rocker arms for specific cylinders. This oil pressure in turn drives synchronizing pistons that connect and disconnect the rocker arms.
The VCM system monitors throttle position, vehicle speed, engine speed, automatic-transmission gear selection and other factors to determine the correct cylinder activation scheme for the operating conditions. In addition, the system determines whether engine oil pressure is suitable for VCM switching and whether catalytic-converter temperature will remain in the proper range. To smooth the transition between activating or deactivating cylinders, the system adjusts ignition timing, drive-by-wire throttle position and turns the torque converter lock-up on and off. As a result, the transition between three-, four-, and six-cylinder operation is unnoticeable to the driver.
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