To gain ground clearance and to create a more level look for my ML320 I adjusted the front torsion bars.
All you need is a 19 mm (or 3/4" ) socket, an extension bar (torque wrench will do as well) and a measuring tape. You'll find the adjusting nuts right under the b-pillar on both sides of your ML. Even if you are not mechanically inclined this job takes only about 10 to 15 minutes.
Front axle clearance including a gain achieved by mounting 265/75R16 tires measures 10.5 inches. Stock tires would account for 1.2" less clearance. Due to the torsion bar adjustment front and rear axle clearance are equal now.
Arrow points to (left) torsion bar.
Make sure the vehicle is positioned on true level ground (concrete floor) and measure during torsion bar adjustment the height from the floor to the inside of the fender well (the adjustment bumped the measurement from 33.7" to 34.5" on my vehicle in combination with 265/75 R 16 tires) Both sides need to be of equal height.
According to the factory specs the torsion bar can be adjusted 1 inch up or down. A re-alignment is recommended after this procedure. I skipped it and found no negative effect yet on my tire wear.