Yep, I know a few X-5 and ML owners who will never buy German automobiles again.
The ML brought a whack of new folks into the showroom, and promptly convinced them that they goofed.
Not only did they take home the least reliable product in MB's line-up, but they got a vehicle equipped with down-market switch gear and interior materials.
Common problems...
1. Check Engine Light. ML owners get sun-burned from the CEL. Mostly things like crank position sensors, Air Mass Meters, Fuel Pressure Regulators and other easily solved (with money) problems. Highly annoying.
2. SRS malfunctions. For some reason, the ML suffers badly from SRS problems. The most common is the failure of the BabySmart sensor in the passenger seat cushion. Easy to fix, just replace the sensor! Just bring money for the part and the labour to take your seat apart and reupholster it!
3. While the 4-matic systems are deadly reliable on the cars, the ML's have some incidences of transfer-case failures.
4. HVAC failures. Evaporator temp sensors break, and always when it's 36C.
5. COMAND screens. All the ML's came with the screen based radio system and I guess they don't age gracefully. Newer ones run the HVAC as well, so you SOL to install an aftermarket radio.
BMW built the X5 to compete with the ML, and for some reason they figured lack of reliability would be one area they'd run with. It's a race to the dealership between the two for a repair...
