Mercedes-Benz M-Class (2005 - 2011) ML420 CDI Sport 5d Tip Auto Owner Review

ML420 CDI Sport 5d Tip Auto

13 October 2019

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In their own words

The V8 diesel engine was the best thing about this W164. It was bloody rapid, it held you and everyone else back in their seats. It beat any Focus ST, Honda Civic Type R, and any Seat Leon Cupra. And the car didn't look any different from the 320CDI Sport. No spoilers - nothing. It was severely understated. The 7G tronic gearbox, the Harman Kardon fibre optic entertainment system, the electrics, the rear SAM module, and that stupid over-cooked and overengineered 'Intelligent' light circuit would never sell me another W164 ever again. The 7G tronic won't live to see another kilometre above 120,000 miles. It is an appalling car. It seemed as if Mercedes deliberately made it fail everything. The V8 diesel engine is welcome to follow me into my next car but it can leave the rest of the W164 behind.

How reliable do you find the car?

The 7G Tronic 722.9 transmission automatic gearbox - any failures or warning lights - sends the 7G and engine straight into limp mode. The fibre optic multi-module Harman Kardon entertainment system packs up - head scratching over weather it's a module or a head unit. Fan blower motor dies through A pillar and windscreen water ingress. Rear SAM module failures through boot water ingress causing a loss of vehicle electrics. Constant Brake Lamp failures on these W164 models due to a stupidly over-complicated rear light circuitry where 21 watt bulbs fit in holders with metal strips which arc and burn themselves out on the circuit board causing unnessesary bulb failures switching to fog lights when there is nothing wrong with the bulb. Electric window failures are also a favourite with this vehicle. Not a reliable car just stay away from Mercedes Benz and look elsewhere if you want a 4x4 of this type. BMW X5, RANGE ROVER, VW TOUREG, PORSCHE CAYENNE are much better and more reliable then these things.

Does the car do everything you expected it to do?

Everything failed! No radio, no left electric window, no de-mister, constant brake lamp warning issues, limp mode issues with the 7G tronic box eventually rendered this car useless and undriveable. The V8 diesel engine and my sun roof were the only best things about this car.

How they rated it
Reliability: 1 out of 5 1.0
Meets Expectations: 2 out of 5 2.0
Overall Rating: 1 out of 5 1.0
Howard Dodds doesn't recommend this car