The Mariner Hybrid delivers essentially the same performance as the gasoline V6, with very little except improved mileage to give away its hybrid powertrain. Few drivers will notice any substantial, functional differences with the Hybrid in day-to-day use. This is a full hybrid, meaning it can run exclusively on electric power, but there's no power cord needed. The battery pack is automatically recharged by the gasoline engine and by regenerative braking, which captures energy that is otherwise wasted when a vehicle looses momentum, then sends it to the batteries for storage.
By combining a four-cylinder gasoline engine with the boost from an electric motor, the Hybrid can deliver a significant fuel-economy improvement and reduce emissions. The Mariner Hybrid can operate on the electric motor up to about 25 mph to maximize in-city fuel economy, and for 2008 it's available with all-wheel drive. .
The Mariner Hybrid's primary source of power remains its gasoline engine. It's nearly identical to the 2.3-liter four in gasoline-only models, except that it runs on something called the Atkinson cycle, which improves its fuel efficiency but reduces horsepower by 20 (to 133). The companion, 70-kilowatt electric motor will kick in when a driver demands full acceleration and deliver more torque to the wheels, or it can power the Mariner Hybrid by itself in certain circumstances, such as creeping along in a traffic jam or rolling through a parking lot. Bottom line, the Hybrid model delivers acceleration times comparable to the gas-only V6, with a 55 percent improvement over gas-only four-cylinder models in city mpg, according to the EPA (34 city, 30 highway for the Hybrid 2WD).
The Hybrid delivers excellent acceleration at lower speeds. Floor it at 20 mph, and it will snap heads back toward head rests. Floor the Hybrid 2WD at a stop sign, and it can squeal its front tires like a hot rod. To be sure, its tires are harder than those on other Mariners and designed for maximum efficiency, which means less rolling resistance, and less grip. The only real performance issue compared to gasoline-only Mariners is a reduction in maximum towing capacity from 3,500 pounds for the V6 4WD (best in class) to 1000 pounds for the Hybrid (still enough for a personal watercraft or dirt bikes)
Few will notice a significant difference between the Hybrid and a conventional Mariner, except when the Hybrid shuts itself off at stop lights or glides quietly through a parking lot on electric power. Indeed, the Hybrid is a bit quieter, probably smoother, in all circumstances. In order to minimize the power lost as it transfers to the drive wheels, the Mariner Hybrid has a continuously variable transmission, which has no conventional gears. Instead, it has metal bands that adjust to best match the engine's rpm. In typical driving, there's no hesitation as gears shift, no uneven surges of speed and less variance in the noise coming from under the hood as the Mariner picks up speed. There's just smooth, even acceleration.
With the stereo cranked up to cover ambient noise, a driver will have a hard time knowing when the gas engine starts or shuts off at stop lights, or when the Hybrid is rolling along on electric power alone. The transitions are generally seamless, and for 2008 models, Mercury engineers spent a lot of time revising the control software to make the changes even less perceptible.
They've done a good job, but we're not sure what protocol determines when the Mariner Hybrid operates on electric power. In fact, it seemed to operate in electric mode less frequently than we might have expected. At times the gas engine ran when we thought it might not have to, and at times it didn't even shut off at a stop light. For the most part, we drove the Hybrid as we would any other test car, which is fairly aggressively, using the accelerator as if someone else were buying the gas, and we still saw some improvement in fuel economy.
Just not an incredible improvement. Our normal rounds include more city than highway driving, though rarely in true rush-hour traffic, plus a few extracurricular, test-specific maneuvers. In this routine, by our best calculation, we found an improvement of 10 to 12 percent over what we've seen with a conventional four-cylinder. We expect most consumers will do better, or at least those with long, traffic-laden commutes. Still, the real-world fuel savings with a hybrid will depend heavily on how, where and when you drive. For guestimation, EPA mileage numbers may be the best tool.
To get the best fuel economy, Hybrid drivers will want to be gentle on the gas pedal. That will maximize the instances when the Mariner travels only on electric power. Dip the pedal quickly, or much past a quarter of its travel, and the gas engine restarts immediately to satisfy what the control electronics determine to be a demand for serious acceleration. Even if a driver is not going to exceed 20 mph, which is well within the limit of electric-only speed, the gas engine will start if the pedal application is too strong. It probably helps to stop slowly, too. Long, steady, coast-down stops, using more engine compression than wheel brakes, are best for charging the batteries. We surmise that short, quick stops from road speeds may keep the engine from shutting off at a red light. The control system may take aggressive stops as an emergency, or just sporting, aggressive driving, and leave the engine fired for more action.
For the best economy, we also recommend the optional navigation system, which on the Hybrid includes an energy-meter function that graphically illustrates how well you're doing at saving fuel. It includes instant and average fuel economy readouts, and tells you when the gas engine is running, when the electric motor is doing the work and when the batteries are charging. It's a good tool to learn how to maximize economy with the Mariner Hybrid.
The other engines in the 2008 Mariner are carryover from the previous generation, but both are decent performers. The base 2.3-liter four-cylinder delivers good power at high revs for those who like to wind it up, and adequate torque at any speed. With a balance shaft to offset vibration, it's also smoother than some of Ford's previous four-cylinder engines. We just wish the 153-hp four was available in the Mariner with the five-speed manual transmission offered in its corporate twin, the Ford Escape. The 2.3 four is more satisfying with a manual, and more fun to drive.
The 200-hp, 3.0-liter V6 engine delivers stronger acceleration, and about as much torque as any small SUV is likely to need. It has no obvious torque peak, or accompanying burst of thrilling acceleration, but its power band is broad. In day-to-day driving, it never lugs, strains or feels as if it's out of breath.
Neither the four-cylinder nor V6 powertrain is the smoothest in small SUVs, but neither is course enough to seriously detract from Mariner's appeal. Our gripe in the driveline is the four-speed automatic, and it's not because some competitors now offer five-speeds. While the Mariner automatic shifts smoothly, it sometimes shifts slowly, in that it seems to take its time deciding what gear it wants to be in. In particular, it's very reluctant to shift itself down into first gear, which would provide the most immediate acceleration. When rolling out of a parking lot onto a busy road, for example, the transmission will stay in second gear when you hit the gas, even when first is better for the traffic conditions.
The automatic is the biggest source of complaint in the Mariner's overall performance, and how much that matters will depend on how you drive. In general, the Mariner handles well, and improvements for 2008 give it a more refined feel. One of those is the electric power-assisted steering system (EPS), which operates with an electric motor rather than a belt turned by the engine. One of the advantages is increased efficiency, because a conventional, belt-driven steering pump takes a bit of the engine's power just to operate. That's power that's not being used to move the vehicle.
In Mariner's case, the electric power steering pump also improves steering feel. With EPS, there's a nice balance between steering assist at parking-lot speeds and decent feel on the highway. The steering tracks more steadily than before, with less adjustment or correction required over uneven surfaces. It's direct and accurate with no dead spot in the center, and there's enough feeling when you turn the wheel to impart a sense of control.
In all, refinements in the steering and suspension improve the 2008 Mariner's performance on the road, which wasn't that bad to begin with. Despite its truck-style ambience, the Mariner delivers a ride-handling balance that comes closer to a sedan than a truck. Its ride is comfortable, but never wobbly or floaty, over a variety of road surfaces, including expansion joints and shallow potholes. The tires deliver respectable grip in paved corners, so the Mariner stays planted where a lot of SUVs might slide. Transient response is surprisingly good, meaning Mariner maintains reasonable composure in a series of left-right-left lane-change maneuvers. This allows quicker driving that is also smooth, and it won't make passengers feel sea-sick.
Mercury pitches the return to drum-style rear brakes on gasoline-powered Mariners as an improvement, claiming the drums add durability and reduce the amount of brake dust generated. We call it a cost-saving move, plain and simple, and that's fine. We also believe consumers are smart enough to know whether they like the cost advantage of drum brakes, or not. No need to spin it.
As it is, the Mariner stops in plenty of time, with no brake fade in any typical on-road driving circumstances. The ABS system is well tuned, keeping the brakes right at the threshold between maximum stopping force and wheel lock, and allowing the driver to maintain steering control in a full-panic stop.
Hybrid or coventional, Mariner makes a good all-season vehicle in all climates. It does not make a good off-road vehicle, despite a bit more ground clearance than some competitors. The optional Intelligent all-wheel drive (AWD) system is tuned for driving more on slippery pavement than dirt or gravel. It monitors vehicle speed, throttle input and steering angle and delivers engine power to the appropriate wheels before any particular wheel can loose traction. It can switch power front to rear or side to side, and theoretically can send 100 percent of the engine's power to either the front or rear wheels.
The system takes a lot of the stress out of driving on wet, slushy or snowy roads. It helps maximize forward progress on slippery surfaces, and its transfer of power to wheels with the best traction is rarely noticed by the driver, who can focus simply on using the gas smoothly and steering between the lines.
Of course, the Mariner is built on a front-wheel-drive platform developed primarily for sedans, and like most small SUVs, the 2WD models are front-wheel drive. With caution, it can handle reasonably level gravel or dirt trails. But if there is no graded path, forget about it, and if the way is much steeper than you'd attempt in a car, forget about that, too. Shoppers seeking a small SUV with real off-road potential should consider a competitor like the Jeep Liberty.
For everyday driving and travel on the road, the Mariner is one of the best. Next Page