Do you have a grinding noise in your 2007-2013 Mercedes 4Matic gearbox? Do you hear a grind that starts at low speed and increases as the car speeds up until it’s so loud you’re afraid to drive it? Many people confuse the noise with wheel bearing failure, but it’s not. The 2008 and new C-Class 4Matics are prone to this same failure. S550 and C300 4Matics are the most problematic. If you’ve got either of those models, read on.
We’ve seen several W221 S-Class Mercedes 4Matics with noisy transmission / transfer case assemblies, and we’re thinking this may become more common as the vehicles age. The cars we’re seeing have 60-90,000 miles on their odometers when they start grinding.
Our most recent client came to us after the local Benz dealer told him he needed a new transmission, because Mercedes didn’t want them making internal repairs. He thought $6,000-some was a lot of money for a bad bearing and he asked if we could help.
Of course we said yes. Lead tech Danny Ferrari in our Mercedes shop removed the transmission and tore it down, whereupon the failure was obvious. The bearings had failed. The ones that carry the transfer case shafts and take the load from the driveshaft had totally come apart. It seemed like an easy fix, but Mercedes does not sell internal parts and they build this gearbox in-house.
We have spent the time to locate sources of original quality repair parts overseas, and we’re now able to fix these formerly unserviceable units. We can generally save you a few thousand dollars over the cost of a dealer exchange part.
Our shop can perform any service or repair on these fine cars, including transmission services. However, there’s no preventative maintenance we know of that will head off this bearing failure. It may be that the load on these bearings is just too much for their size, or there may be another cause.
If you've got an older Benz, look to us for transmission fluid flushes, filters, repairs to the sensor plate, and repair of leaking electrical feed-through connectors. The older Mercedes transmissions are showing more problems because the years and miles are piling up, but we can fix anything that happens to them.
From what we can see the repaired transmissions will last as long as the originals, and repair takes less than a week, start to finish, for most units. J E Robison Service is a Bosch Car Service specialist in Springfield, MA. Find us at 347 Page Boulevard, in the Springfield Auto Complex, in Springfield, MA 01104.
Robison Service has provided independent service, repair, and restoration for Mercedes Benz owners all over New England for over 25 years. We also service BMW, MINI, Jaguar, Land Rover, Porsche, and Rolls Royce and Bentley motorcars. We have flatbed transport all over the region. We also offer pickup and delivery for cars in Springfield, Wilbraham, Longmeadow, Agawam, Westfield, Northampton, and Amherst.
Visit us online at www.robisonservice.com or call 413-785-1665.
(c) 2014 John Elder Robison