Product Liability

Mercedes-Benz Sued Over Allegedly Dangerously Defective Transmissions

mercedes Mercedes Benz Sued Over Allegedly Dangerously Defective TransmissionsCertain Mercedes-Benz vehicles with 722.9 7G-Tronic transmissions are the basis of a class-action lawsuit alleging the transmissions have a dangerous defect that allows them to suddenly slip into low gear and fail prematurely.

The class-action covers owners and lessees of Mercedes vehicles with the allegedly defective transmissions in California and Kansas.

According to, the lawsuit alleges that technical service bulletins Mercedes sent to dealerships show that the automaker knew of the safety defect yet took no measures to warn its customers or recall the vehicles. The safety defect is so common that at one point Mercedes was unable to keep up with orders for replacement transmissions.

Defective valve bodies and conductor plates in the transmissions pose a serious safety issue, the lawsuit alleges, because it can cause the vehicle to unexpectedly slip into what Mercedes calls “limp mode” and become stuck in the lower gear. published some of the problems drivers of 2006 Mercedes-Benz ML350 vehicles reported to the National Highway Traffic Safety Administration (NHTSA). The auto blog gives the defect a severity rating of 10 out of 10, indicating the problem is “really awful.”

One driver writes:

“I was nearly rear-ended by a tractor trailer while entering I-91 in [Connecticut] just last week when the vehicle unexpectedly went into what mb calls ‘limp mode’ when the check engine light comes on and the vehicle speed is restricted to 30 mph immediately.”

The same driver adds,

“There is a systemic problem with the Mercedes Benz 7G tronic 722.9 transmission control module which causes the vehicle’s transmission to, without notice, fail to shift out of 2nd gear which creates a serious safety hazard while driving including entering the freeway and attempting to merge into traffic.”

Plaintiffs also accuse Mercedes of barring independent repair shops from buying 722.9 transmission replacement parts, forcing them to use Mercedes dealerships for repairs and paying substantially more for the repairs.

They also claim the automaker failed to take action to fix the dangerous transmissions, especially when the failures occurred outside the warranty period, according to

The class-action was filed in federal court in San Jose, California.