I had a 2007 ML 320CDI for 70k miles and traded it on a Cayenne. Big mistake.

The two issues I had with the ML were the air suspension - fixed after 3-4 upgrades on the compressor. The other is the 7-speed transmission. After several firmware upgrades and a switch to the newer ATF formulation, it was somewhat better but still harsher shifting that it should have been; and it hunted for the right gear on occasion - not up to the standards I would expect from MB.

After my extreme dissatisfaction with the Cayenne I would have purchased another ML CDI, but the run flats were the deal breaker.

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1973 280SE 4.5 (Sold)
1984 LWB 280GE (Sold)
2000 G500 NMLE - "Deep Throat"
2007 ML320 CDI (Sold)
2010 Porsche Cayenne S Transsyberia TipTronic (Sold)
2010 Audi Q7 3.0 TDI (Sold and Sorely Missed)
2014 ML350 BTC
2015 Audi Q7 3.0 TDI (On Order)