Subframe, Removing and Installing

Subframe, removing and installing





Special tools and equipment
^ 10-222 A Support bar
^ 10-222 A/1 Legs of support bar
^ 3393 Testing mandrels

Removing





- Support engine with support bar.
- Remove wheel trim; pull trim cap off light-alloy wheels (puller in vehicle tool kit).
- Remove wheels.
- Secure brake disc with wheel bolt.
- Remove noise insulation tray.





- Before disconnecting subframe, use special tool 3393 to check whether holes -1- and -2- match. If they do not, you must perform wheel alignment after the subframe is re-installed.





- Loosen nuts -arrows- on transmission mount.





- Unscrew nut -1-.

Note: For vehicles with headlight range control, refer to Lighting and Horns, Head Lamp Sensor, Service and Repair.





- Unscrew bolt -5- for ABS speed sensor.
- Unscrew hex bolt -2-.
- Pull wire of ABS speed sensor out of holder at wheel bearing housing.





- Unscrew bolts -1- for brake caliper and remove brake caliper.

Note:
^ Use binding wire to attach brake caliper to body.
^ Never leave brake caliper hanging from brake hose.





- Unscrew bolt -1-
- Unscrew bolt -4-
- Unscrew bolt -3-

Note: To avoid damaging joints of upper links, provide support e.g. using VAG 1383-A (engine and transmission lifter) to guard against excessive rebound.

- Loosen bolted joint between guide link / subframe.
- If necessary, remove tunnel crossmember.





- Unscrew hex bolts -1-.
- Loosen hex bolts -2- and lower rear subframe.
- Remove hex bolts of guide link.
- Pull guide link out of subframe.

Note: Secure joints of track control link and guide link to body using binding wire to protect them from excessive bending.





- Remove cable -arrow- from console





- Unscrew bolt -3-
- Loosen hex bolts -2- until subframe can be removed.

Installing

Note: Always replace nuts and bolts.





- Insert subframe and install hex bolts -5- and -6-.
- Install hex bolt for securing suspension strut to track control link
- Insert track control link and guide link in subframe.
Before tightening subframe, locate it in body using special tool 3393.





- Hole -1-, hole -2- of subframe and hole -3- of aluminum console must all be aligned on both sides.

Note: This locating process is only a substitute for subsequent wheel alignment if:
^ Only the subframe has been removed and installed.
^ Holes -1- and -2- matched before repair.





- Install hex bolts -1- and -2-.
- Apply anti-corrosion agent to hole in body for holding special tool 3393.





- Screw nut -1- tight





- Tighten nuts for transmission mount, if applicable





- Clip cable -arrow- to console

Tightening sequence/tightening torques
Threads in bodywork can be repaired using a threaded wire insert as per DIN 8140 (Heli-Coil). The Threaded insert must be of the same length as the thread in the bodywork.

Bonded rubber bushings can only be turned to a limited extent. The bolted joints at the suspension links are therefore not to be tightened until the vehicle is standing on the ground.





- Tighten hex bolts -2- and -5- to 110 plus additional 90° turn.
- Tighten hex bolts -1- to 55 Nm.





- Tighten nuts for transmission mount to 27 Nm





- Tighten bolt -2- to 75 Nm
- Tighten nuts -1- of engine mount to 23 Nm.





- Give hex bolts -3- for track control link a further turn to 80 Nm plus additional 90° turn.
- Tighten hex bolts for guide link to 90 Nm plus additional 90° turn.
- Tighten link to stabilizer bar -4- to 50 Nm plus additional 90° turn.
- Suspension strut to track control link: 90 Nm





- Tighten sensor -5- to 10 Nm
- Screw brake caliper to wheel bearing housing
- Install wheel and tighten to 120 Nm.