Audi A4 Owners & Service Manuals

Audi A4: Underbody Trim Panels, Removing and Installing

Audi A4 (B9) 2016-2025 Service Manual / Body / Body Exterior / Exterior Equipment / Underbody Trim Panels, Removing and Installing

Underbody Trim Panel, Removing and Installing, Front

Removing

- Remove the nuts -arrows-.

- Remove the front underbody trim panel -2- from the center underbody trim panel -1-.

A66-11721

Installing

Install in reverse order of removal.

Tightening Specifications

  • Refer to → Chapter "Overview - Underbody Trim Panels"

Underbody Trim Panel, Removing and Installing, Center

Removing

- Remove the nuts -arrows- and the bolt -2-.

- Remove the center underbody trim panel -1-.

A66-11634

Installing

Install in reverse order of removal.

Tightening Specifications

  • Refer to → Chapter "Overview - Underbody Trim Panels"

Underbody Trim Panel, Removing and Installing, Rear

Removing

- Remove the nuts -2 and 3- and bolts -1-.

- Remove the rear underbody trim panel -4-.

A66-11700

Installing

Install in reverse order of removal.

Tightening Specifications

  • Refer to → Chapter "Overview - Underbody Trim Panels"

Underbody Trim Panel, Removing and Installing, Side

Removing

- Remove the nuts -3- and bolts -1-.

- Remove the side underbody trim panel -2-.

A66-11722

Installing

Install in reverse order of removal.

Tightening Specifications

  • Refer to → Chapter "Overview - Underbody Trim Panels"

Tunnel Brace, Removing and Installing

Removing

- Remove the bolts -arrows-.

- Remove the tunnel brace -1-.

A66-11723

Installing

Install in reverse order of removal.

Tightening Specifications

  • Refer to → Chapter "Overview - Underbody Bracing"

Diagonal Braces, Removing and Installing

  Caution

This procedure contains mandatory replaceable parts. Refer to component overview and parts catalog prior to starting procedure.

Mandatory Replacement Parts

  • Bolts - Right Diagonal Brace to Body
  • Bolts - Left Diagonal Brace to Body

Removing

  NOTICE

Risk of damaging the thread by using an impact wrench.

- When installing, position the bolts by hand and screw in the first threads.

- Do not loosen or tighten the bolts with an impact wrench.

- Remove the bolts -1 and 3- and remove the diagonal braces -2 and 4-.

A66-11701

Installing

Install in reverse order of removal and note the following:

Tightening Specifications

  • Refer to → Chapter "Overview - Underbody Bracing"

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