2012 Mercedes-Benz GL450 Repair and Maintenance
A guide to problems, costs, maintenance and repair for your 2012 Mercedes-Benz GL450
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2012 Mercedes-Benz GL450 ProblemsRough Shifting of Automatic Transmission
Vehicles equipped with a 7-speed automatic transmission may develop a rough shifting condition, most commonly going up from first to second gear and going down from third to second or second to first gear. Our technicians tell us this is due to an internal component failure. Mercedes has released updated parts; the transmission will need to be removed and disassembled to complete the necessary repairs.
An engine Oil leak may develop from the PCV vent housing on the valve cover and/or the inspection plate on the front of the engine.
The Mercedes Benz GL450 may have engine oil seeping or leaking from the back of the cylinder heads. This is commonly misdiagnosed as leaking valve covers.
On the back of the cylinder heads there are three, in total, plastic expansion plugs that plug access ports to the camshafts. These plugs are well known for seeping oil, and leaking if left unattended. The oil will run down the back of the engine and eventually make it to the ground.
Replacement of these three plastic plugs is extremely simple, and should be done as regular maintenance. The recommended interval for replacement is every 60,000 miles.
2012 Mercedes-Benz GL450 QuestionsDo these vehicles have lots of air suspension problems? (1 answer)
I replaced one of the rear air bags and the compressor and had the suspension calibrated. now one of the front air bags is blown out. is it common to have to replace all of the air bags ?
I just bought it from a used dealership. Nov 15th 2014
The SUV is flooded but it appears the water did not get inside since it still smells like new in there.
2012 Mercedes-Benz GL450 RecallsDriver's Frontal Air Bag Inflator Ruptures And Sprays Metal Fragments
The driver's frontal air bag inflator may deploy the air bag with excessive pressure, resulting in the inflator rupturing and causing metal debris to be sprayed onto vehicle occupants. Dealers will replace the driver's frontal air bag module free of charge to resolve the concern.