With the introduction this fall of its new ML320 sport-utility, Mercedes-Benz faces a technical question that automakers rarely get to ask and answer: How do you learn to service vehicles in a new segment?
Carmakers introduce new models all the time. And each new generation of technology carries some uncertainty about how a product will perform over the long run, and what its service requirements will be.
But the new Mercedes vehicle represents not just a new model, but a new type of vehicle for the company. It is Mercedes' first entry into the off-road, four-wheel-drive light-truck segment.
This fall's launch will bring Mercedes into a customer population that is essentially an unknown commodity for the company and its dealers, although market research assures Mercedes-Benz that a large percentage of its car owners are already driving sport-utilities from other manufacturers.
The new M class will be the first chance many Mercedes service technicians have to work on a light truck. Adding to that challenge, Mercedes officials say they hope the new sport-utility will give dealers an incentive to reach a higher level of customer satisfaction.
But as the M class nears its September market introduction, Mercedes is downplaying the significance of the ML320's service-depart- ment differences. Its engine, company managers note, will be shared by the CLK, the C280 and the E-class wagon. Its four-wheel-drive capability is not unfamiliar - past cars have had 4Matic four- wheel-drive systems, and later this year, the E320 will have four-wheel drive again. And the ML320's four-wheel antilock braking system is shared with other Mercedes vehicles.
Key differences for technicians, according to Alan Apel, assistant manager of worldwide service training at the manufacturing company, Mercedes-Benz U.S. International Inc. in Vance, Ala., will be a new transfer case and some of the vehicle's electronics.
The transfer case allows an ML320 driver to shift down into an ultra-low off-road gear that enables the vehicle to claw its way up muddy hillsides or creep down sheer inclines.
Apel says the vehicle's service manual is being drafted. He adds that the company has not determined what kind of training - or what duration - will be needed to prepare technicians for the new product. But the vehicle's designers have simplified at least one service issue for the technicians - when to change the oil.
The ML320 is the first Mercedes product to contain what U.S. product managers call the 'Flexible Service System,' or FSS. The system takes the arbitrariness and guesswork out of making an oil change. Rather than assign a specific schedule to the vehicle's oil life, the FSS lets each vehicle set its own maintenance schedule.
Rather than bringing in the sport-utility for a change at, for example, 7,500 miles, 10,000 miles and 12,000 miles, the FSS informs the driver when the oil needs changing, based on the specifics of that owner's driving habits.
The system goes beyond the oil monitors that are now on many cars. Those, for the most part, monitor oil levels, telling the driver when the level has dropped. The Mercedes version monitors the quality of the oil in the vehicle's veins.
That technology serves two purposes, explains Robert Allan, assistant product manager for parts and components with the vehicle's retailer, Mercedes-Benz of North America Inc.
First, it creates goodwill with the new owner. 'The idea was to help decrease the service requirements of the car, and literally custom-tailor it to the vehicle,' Allan explains. 'People don't like taking their car in for servicing. A lot of folks have busy schedules. This system can actually extend the schedule for taking the car in.'
Second, it gives Mercedes-Benz flexibility on servicing the new products. Because the sport-utility customer base is relatively unknown to the company, there will be some unanswered questions surrounding the use of the M class, Allan acknowledges. Will owners drive it hard? What percentage will take it out and jostle it around over rough terrain? Or will they pamper it, reserving it for short drives - the sort of five-minute starts and stops that build up condensation in the oil?
'They may be carrying a lot more weight and luggage along with their vehicle,' Allan says of the potential new customers. 'They'll be using it a little differently from their passenger car.'
How it works
The new oil system - which will begin appearing on other Mercedes products in the months to come - operates like this:
An analog sensor is located inside a polymer tube inside the vehicle's oil reservoir. The sensor evaluates the oil's quality by looking for impurities, using a numeric-value system to assign the oil to a sort of quality scale. One numeric value represents black sludge. At the other end of the scale, another numeric value represents new clean oil.
The sensor measures the oil's level, its conductivity, and particulates such as nitrates. At the same time, different sensors read the oil temperature, as well as the temperature of the engine coolant, the engine speed, the road speed and the engine load. Sensors also look at the number of starts and stops the driver makes.
The information is collated in a microcomputer, which calculates how much more oil is available for driving under various conditions. All of this is done once every 300 milliseconds. The system then projects how many more miles or days of driving are available until the oil should be changed. When the recommended date is 30 days away, a dashboard message begins a countdown.
Allan explains that the constant analysis prevents drivers from changing their oil unnecessarily. Mercedes chose a baseline of 7,500 miles for the oil change. But drivers may end up changing it at 10,000 or 12,000 miles, depending on their driving.
'The bottom line is conservation of oil and lowering of service requirement costs,' he says. 'It helps the customer because they only get this service based on needs of their particular vehicle.'
It also serves as a trouble indicator for the dealership technician.
And it serves to remind customers in exact days or miles of when they need to schedule maintenance at the dealership. If the system indicates that the oil quality is deteriorating too rapidly, the technician would know to look for a cause.
Automotive News Staff Reporter Lindsay Chappell is based in Nashville, Tenn.