I had the same drag or tire scrubbing effect when pulling out of a parking space. I have a 99 ML320 with 40,000 miles on it. I brought it to the dealer and had a shop tech test drive it with me in the car (he drove). Right out of the parking spot he felt the shuddering (like if 4wd was turned on). It ended up getting a new transfer case and output shaft bearing.

When I picked up the ML it was like driving a new car. It seemed to roll much easier and my gas mileage went up 2 - 3 gallons on local driving. I was getting 15mpg avg around town, I now get 17 - 18mpg.

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1990 300CE-24
2003 SLK230 (Sport - 6spd)
1995 Ford Thunderbird