The Evolution of Mercedes-Benz Modular Front-Wheel-Drive Architecture – The A, B & CLA Classe

Richard Simonds

_66 background FLAT.jpgIn Europe the company began nurturing the idea of a high-end compact in 1997 by introducing two model generations of the A- and B-Class, built on what was called “Modular Front-wheel-drive Architecture,” or MFA. As a small test, the second-generation B-Class was offered on these shores, but only in Canada. It wasn’t until 2014 that the CLA was introduced in the United States, the first front-wheel-drive Mercedes-Benz ever sold in this country.


The Evolution of Mercedes-Benz Modular Front-Wheel-Drive Architecture

The A, B & CLA Classes


The sixth in an ongoing series of reference guides tracing the development

of the current Mercedes-Benz product range by model and chassis number


Article Richard Simonds & Gary Anderson

Images Daimler Global Media

Illustration Stephan McKeown



Mercedes-Benz Automobiles makes major changes in design and engineering only sparingly – and even then, very cautiously after careful consideration. When the company introduced the W120 unit-body chassis on the ponton-bodied W180 in 1953, it continued to produce body-on-chassis cars with separate front and rear fenders for several more years – just in case customers were reluctant to buy cars with the new innovation. In the same way, when the Mercedes-Benz directors’ board made the decision in the late 1990s to offer a compact car alongside its medium- and large-size models, the transition was equally cautious.

The primary challenge in developing a car is that the smaller package dictates a transverse-mounted, 4-cylinder engine with front-wheel drive, three engineering practices that were unprecedented in the company. Having nurtured an image of selling full-size luxury cars to affluent customers, Mercedes-Benz dealerships – especially in the United States – were concerned that a front-engine compact on their showroom floors might dilute the prestige of the marque. In their view, these cars were the very essence of entry-level economy.

Nevertheless, in Europe the company began nurturing the idea of a high-end compact in 1997 by introducing two model generations of the A- and B-Class, built on what was called “Modular Front-wheel-drive Architecture,” or MFA. As a small test, the second-generation B-Class was offered on these shores, but only in Canada. It wasn’t until 2014 that the CLA was introduced in the United States, the first front-wheel-drive Mercedes-Benz ever sold in this country.


First-generation A-Class – 1997-2004

A subcompact front-wheel drive vehicle that had versatile configurations and met Mercedes-Benz safety standards had never before been considered. To break the ice, the company brought the “Vision A 93” concept vehicle to the International Motor Show at Frankfurt in September 1993. Having typical Mercedes-Benz attention to detail, the concept received overwhelming positive reviews from the public and automotive journalists. In 1994, the revised “Studie A” version debuted at the Geneva Motor Show to further acclaim and was named “Best Concept Car 1994” by Motor Week magazine – published in the United States. Press releases and a media campaign started in December 1996 to introduce this all-new Mercedes-Benz model to the public in select markets.

The A-Class (W168) was introduced in Europe in 1997 as a front-wheel-drive five-door hatchback in the subcompact category. Clearly, the image preparation with the concept cars was successful; the A-Class sold more than half a million units in its first four model years. To produce the car, the company added 1,600 new assembly-line workers and 600 administrative personnel at the factory in Rastatt, Germany, and soon procured production facilities in Brazil and Thailand. By May 2004, the Rastatt factory had produced 882,661 standard-wheelbase models and 202,212 long-wheelbase models. The Brazil factory produced another 63,448 models through September 2005, with Thailand producing a comparable number.

Reflecting the Mercedes-Benz commitment to safety regardless of size, the A-Class was designed with a major advance in FWD architecture: In the event of severe frontal impact, the transverse engine would roll up to 59 degrees forward and with the transmission, would slide under the two-layer “sandwich” floor rather than into the passenger compartment – a breakthrough for a subcompact vehicle with limited crumple-zone space. This Modular Front-wheel drive Architecture, now referred to simply as MFA, was the basis for all A- and B-Class vehicles.

Unfortunately, the A-Class initially was found to roll over when it swerved under extreme circumstances to avoid an obstacle in the road. In the first reviews, a Swedish magazine referred to this as the “moose test.” To its credit, Mercedes-Benz recalled all 2,600 initial units that had been sold; the company modified the suspension and added Electronic Stability Control. Situation fixed!


Second-generation A-Class – 2004-2012

The second-generation A-Class launched in September 2004 added a sporty, youthful three-door hatchback coupe (chassis designation C169) in the subcompact category. This model came with only one wheelbase (101.1 inches), an inch shorter than the long-wheelbase model in the first generation.

A 6.7-inch (170mm) longer wheelbase on the five-door model (chassis designation V168) offered even more versatility, upping the A-Class into the compact category. This version offered the comfort and appearance, as well as roominess of a mid-size sedan. The rear seats were on a track that allowed them to be moved fore and aft 4.4 inches (111mm) to accommodate passenger legroom or cargo capacity; even in their most forward position, passengers had more legroom than in the standard wheelbase version with its fixed seats.

The safety features of the sandwich floor and engine mounting continued to provide exemplary safety protection for passengers. Customer choices for car models expanded to include six engine variants at launch (three gasoline and three diesel), and three design and equipment levels available – Classic, Elegance and Avantgarde.

A fourth gasoline engine, the A200 Turbo, was launched for the 2005 model year. Again, there were numerous technological improvements, not the least of which was the 38-percent increase in engine output while delivering improved fuel economy.

Engineering and manufacturing quality were evident in the sales figures of the A-Class (W169); 10 weeks after introduction, 50,000 orders had been placed. One-year after launch, 200,000 vehicles had been delivered; two years after launch, 371,700 customers had purchased the new A-Class. By September 2007, 500,000 A-Class units had sold.

The A-Class was updated in April 2008 with significantly more standard equipment. The Start/Stop function was added to improve fuel economy in city driving; Active Park Assist enabled the car to parallel-park itself with only throttle and brake input by the driver.

The A-Class E-Cell, an all-electric vehicle, debuted at the Paris Auto Show in October 2010. It had a range of about 120 miles using a power train developed by Tesla Motors as part of a collaboration agreement between the two companies. Mercedes-Benz engineers created a modular system for electric vehicles that allowed the efficient use of shared parts in the A-Class E-Cell, the B-Class F-Cell and E-Cell, and the Smart “fortwo” electric drive. Later, the CLA-Class and GLA-Class shared this modular system. The A-Class was used as the platform for proof-of-concept for the first practical hydrogen fuel cell power train, tested by the Mercedes-Benz Research & Development facilities in Long Beach, California, as part of the Fuel Cell Consortium research program. Other than that, the A-Class was never brought into the United States as a dealer-supported product.

By June 2009, 750,000 second-generation vehicles had been built at the Rastatt factory and on February 1, 2012, the one-millionth second-generation A-Class (W169/C169) had been produced.

Third-generation A-Class – 2012-present

The W176 A-Class was unveiled at the Geneva Motor Show in March 2012 and put into production that September. It has an entirely different design with more rounded contours and a more vertical grille to harmonize with other models in the Mercedes-Benz family (such as the B-Class and C-Class). Though the collapsing engine suspension was retained for safety, the use of a multilayer sandwich floor pan was discontinued. This third-generation sedan has a 106.3-inch wheelbase and is 169 inches long, making it a full-fledged family sedan. It is offered in Europe with a 6-speed manual or the 7-speed automatic that is used throughout the Mercedes-Benz line.

It continues to be produced in Rastatt as well as in the South America and Asia plants, but to meet high demand in Europe, the third-generation A-Class is also produced by Valmet Automotive in Finland, where the company targeted building 100,000 units between 2013 and 2016. With the introduction of the CLA in the United States, there are no plans to market the A-Class model here.


First-generation B-Class – 2005-2012

Having successfully proven that Mercedes-Benz could market a subcompact front-wheel-drive car, at least in Europe, the company introduced the B-Class (T245) as a five-door sports compact tourer in spring 2005. Based on the second-generation A-Class with sandwich-floor unibody, it was marketed as a compact luxury car with many amenities found in the larger sedans. It could serve as an urban-suburban family car or a utility vehicle with a sporty design and performance to match. Though U.S. dealers, concerned about the impact it might have on their upscale image, spurned the new hatchback, the new B-Class was introduced in Canada that autumn.

In March 2008, an updated B-Class T245 was released in Europe with minor design changes; a new natural-gas engine that could also run on gasoline, a start-stop option, a “BlueEfficiency” gasoline-engine option, and other technologies that were being introduced by Mercedes-Benz across all models.

The first-generation B-Class was used as the basis for a prototype hydrogen-fuel version. To prove the reliability of hydrogen-fuel cars, three “F-cell” B-Class vehicles were driven around the world in 2011 without any problems; The Star magazine editor drove one of the vehicles on that tour from New Orleans to San Antonio.


Second-generation B-Class – 2012-present

In 2012, a second-generation B-Class on the T246 chassis was introduced for the European market. It was larger, yet had a lower coefficient of drag that benefited fuel economy and reduced wind noise. The model could be ordered with either gasoline or diesel engines – as well as natural-gas engines for industrial use and government agencies – with either 6-speed manual or 7-speed dual-clutch sequential automatic transmissions, powering either the front wheels or in a 4Matic version.

In addition, by the end of 2013, a battery-electric version was offered for the first time. The concept of a B-Class electric drive had been introduced at the 2012 Paris Motor Show, the 2013 New York International Auto Show and the 2013 International Motor Show (IAA) in Frankfurt.

In late 2014, the all-electric E-Drive B-Class models were introduced in the U.S. market as 2015 models, with the battery packs built into the sandwich floor. The E-Drive B250e has an EPA range of 87 miles (120 miles using German testing) and a top speed of 93 mph with a Tesla-sourced lithium-ion battery pack and motors that produce 177 horsepower and are rated at 84 MPGe. In 2015, more than 1,900 B250e vehicles were sold in the United States – the only B-Class model imported by MBUSA. Withdrawn from the Canadian market when the CLA was introduced, the internal-combustion B-Class is no longer available in North America.


First-generation CLA – 2013-present

Still believing that opportunity existed for a compact car with the Mercedes-Benz upscale product image in the United States, the company used the concept-car strategy again. In 2012, Mercedes-Benz unveiled a new model styled after the high-end CLS four-door coupe at the Pebble Beach Concours d’Elegance. Then in a major advertising initiative that began with the 2013 Super Bowl, the company began touting its price – “A Mercedes-Benz for under $30,000.” The car was launched at U.S. dealerships in September, five months after its introduction in Germany.

The CLA has the MFA chassis with a 106.3-inch wheelbase. The overall body is 182.3 inches long (more than 13 inches longer than the third-generation A-Class on which it shares a platform). MBUSA offers the CLA250 with the 2.0-liter, twin-turbo, 4-cylinder gasoline engine, and as the CLA45 AMG with the AMG-tuned version of the modified engine. Available with front-wheel or 4Matic all-wheel drive, both versions share a 7-speed dual-clutch automatic transmission. The AMG version has other performance modifications, including a SpeedShift DCT 7-speed automatic, sport suspension and high-performance tires, sport brakes, sport steering, with interiors and body cladding that displays its AMG bona fides.

More than 100,000 units of the CLA were sold in its first year, making it “the best launch in 20 years” by Mercedes-Benz.

GLA – sport-utility variant of MFA chassis

The GLA, while technically an SUV, is closer to the A/B/CLA class than it is to the GL class. To capitalize on U.S. demand for sport-utility vehicles and to assuage dealers who didn’t want to offer a hatchback sedan, the firm presented a high-clearance muscular-styled compact SUV – the GLA – based on the CLA’s flexible MFA classis, as a concept at the 2013 Shanghai Auto Show; the AMG version debuted at the 2013 Los Angeles International Auto Show. With SUV styling, hatchback packaging became more acceptable to U.S. dealers. Production models, closely following the product offerings of the CLA and CLA45 AMG, became available in autumn 2014 and are selling well.