Wheel alignment

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Wheel Alignment

http://www.jltechno.com/en/alignment-data-lookup

Tutorials

Four wheel alignment using a laser machine
MB guide to effective wheel alignment

DIY toe-in measurement

Trackace DIY laser wheel alignment tracking gauge (~100 EUR) is a cheap, simple and precise measurement tool to measure front wheel's toe-in/toe-out.

According to W220 specifications, the front wheels should have toe in of 0° 15'(± 10').

DIY toe-in measurement using trackace
Trackace toe-in measurement (reads ~25')
Trackace DIY Laser Wheel Alignment
To adjust use 21mm and 13mm wrenches

Airmatic height setting

Toe-in on a raised and lowered car (Airmatic level adjustment) can differ. On some cars we have observed that it differs just a little (around 5') while on other W220 vehicles toe-in on a raised car can be even 20' larger than on a lowered car. This should be taken into account when performing a toe-in adjustment. I.e., the toe-in should be adjusted for the Airmatic height setting that is usually used for driving. If both height settings are used equally, then the toe-in should be set to have the same distance from the targeted toe-in (0° 15') on a lowered and raised car.

Adjust toe at the front axle (FA)

Adjust:

  • Switch off easy entry/exit for driver seat and steering wheel. Otherwise the driver seat and steering wheel move into a different position if the driver door is opened or closed for example. The upper frame may be damaged when the holding device (055) is installed. Switching off takes place via the buttons on the steering wheel in the "comfort" menu of the multifunction display.
  • Swivel sun visor to one side and fix steering wheel in center position using retainer (055). Carefully mount retainer (055), in order to avoid damaging the steering wheel or the headliner.
  • Check center position of steering gear and steering wheel. The steering gear is centered when the marking on the cap is aligned with the mark on the control valve housing. If necessary, shift steering wheel.
  • Install wheel spreader (030) at the front in the direction of travel on the inside of the wheel (in the direction of travel). The elastic bearing of the transverse control arm and steering linkage produces a correspondingly large toe value that is reduced to the correct dimension in the ready to-drive condition.
  • Counterhold tie rod (10) at the hexagon and loosen jam nut (10f).
  • Rotate the tie rods (10) to adjust the toe angle.
  • Tighten jam nut (10f)
  • Remove retainer (055).
  • Remove wheel spreader (030).
  • Check bellows for twisting and align if necessary.

Front axle toe check values: 0° 15'(± 10')

Torque spec:

  • Lock nut, tie rod to inner tie rod: 60 Nm
  • 055 - Retaining device
  • 055b - Mounting

Shown on model 220 without 4MATIC

  • 10 - Tie rod
  • 10f - Locknut

Shown on model 220 with 4MATIC

  • Arrows - Center position of steering

Shown on model 220 without 4MATIC

  • 030 - Wheel spreader

Adjust toe at the rear axle (RA)

Rear axle toe check values: 0° 41'(± 14')

This is an average value. More specific rear toe angle values (depending on vehicle level) are listed in WIS.

Adjust camber and caster at the front axle (FA)

Shown on model 220 with AIRMATIC

Camber

  • 17 - Spring control arm
  • 19b - Nut
  • 19c - Repair bolt
  • 19d - Shims
  • St+ - Positive camber
  • St- - Negative camber
  • a - Adjusting the spring control arm towards the vehicle center causes a positive camber change
  • b - Adjusting the spring control arm towards the outside of the vehicle causes a negative camber change

Shown on model 220 with AIRMATIC

Caster

  • 18 - Torque strut
  • 19b - Nut
  • 19c - Repair bolt
  • 19d - Shims
  • NL - Caster
  • a - Adjusting the strut rod toward the center of the vehicle increases the caster
  • b - Adjusting the torque strut towards the outside of the vehicle reduces the caster

Adjust:

  • Install repair bolt (19c). Screw on nut (19b) until it abuts, but do not tighten yet so that the rubber mount of the torque strut (18) or spring control arm (17) can twist when the vehicle is rocked to settle the suspension.
  • Recheck vehicle level at front axle after adjusting the camber and caster. The vehicle level must match the dimension established during the initial measurement.
  • Tighten nut (19b). The repair bolt (19c) must not turn after fixing. When tightening the nut (19b) counterhold the repair bolt (19c) otherwise the lock tabs in the rubber mount of the torque strut (18) or spring control arm (17) will be sheared off.

Torque specification:

  • Repair kit nut: 120 Nm


Check values:

  • Camber check value: 1°N±20' (tolerated difference between left/right: 0°20')
  • Caster check value: 9°11'±30' (tolerated difference between left/right: 0°30')

These are average check values. More specific values (depending on vehicle level) are listed in WIS.


Install repair bolt

Camber adjustments
Spring link in mm Camber change Torque strut in mm Caster change
+4 -26' ±0 +35'
-4 +26' ±0 -35'


Caster adjustments
Spring link in mm Camber change Torque strut in mm Caster change
±0 -5' +4 -46'
±0 +5' -4 +46'


Caster adjustments
Spring link in mm Camber change Torque strut in mm Caster change
+4 -31' +4 -11'
-4 +31' -4 +11'
+4 -21' -4 +1°22'
-4 +21' +4 -1°22'

1. Jack up vehicle at the front (the suspension must be fully rebounded).

2. Vehicles with ABC suspension: To remove the production bolt (19a) of the right front spring link, detach the bracket of the valve unit for pressure supply (52) from the front axle carrier.

  • 19a - Production bolt
  • 52 - Pressure supply valve unit
  • 52/1 - Mounting bolts of the bracket of the valve unit for pressure supply

3. To adjust the camber and caster, the respective production bolt (19a) on the torque strut or spring link must be replaced with a repair bolt (19c).

  • A - Standard bolted connection
  • B - Repair bolted connection
  • 19a - Production bolt
  • 19c - Repair bolt
  • 19b - Nut

The standard bolt (19a) is centered by the bumps (arrows) in the bearing of the torque strut or spring link. Grooves in the repair bolt (19c) permit it to be installed in the bearing on either the right or left side, allowing the torque strut or spring link to be adjusted by a distance of 4 mm to the inside or outside.

The repair bolt (19c) must not be turned after the torque strut or spring link has been fixed in the bearing. Do not tighten the nut yet so that the rubber mounts on the torque strut and spring link can turn when the suspension is compressed and rebounded.

Fitted bolt (A2203330171)

Adjust camber at the rear axle (RA)

On the rear axle camber cannot be adjusted.

Rear camber check value: 1°6'N±30' (tolerated difference between left/right: 0°30')

This is an average check value. More specific values (depending on vehicle level) are listed in WIS.