Chassis Support / Floor Pan Reinforcement Strut – 4K0803145

Original chassis structural support / subframe and floor pan reinforcement crossmember (lower front suspension load-bearing strut / tunnel and skid plate reinforcement), designed for Audi A7 Sportback (4K / 4K8 generation) and Audi A6 C8 (4K2 / 4K5 / 4KA type) models produced from 2018 to 2026, including versions with 3.0 V6 TFSI (55 TFSI), 2.0 TFSI, TDI engines, and top-tier S and RS models, based on the modular MLBevo longitudinal platform.

Original VAG chassis structural and load-bearing component. Made of high-strength pressed structural steel alloy, protected against corrosion by a factory cataphoretic (KTL) coating. Mounted underneath the vehicle between the frame longitudinals, subframe (suspension skid), and floor pan. It is responsible for directly stiffening the front section of the bodywork against torsion, stabilizing suspension geometry under high longitudinal and lateral loads, and absorbing collision energy, while also providing a solid load-bearing base for the lower engine and gearbox soundproofing covers.

Technical specifications:

• Catalog part number (OE): 4K0803145 / 4K0 803 145 (interchangeable with revisions in the 4K0803145A, 4K0803145B, 4K0803145C series)

• System / Category: Chassis and suspension components / Beams, subframe supports, and frame reinforcements (Underbody Crossmember / Subframe Diagonal Strut Support)

• Function: Strut / support stiffening the chassis and subframe

• Material: Durable pressed structural steel with a factory KTL anti-corrosion coating

• Side / Mounting location: Underside of the vehicle – front area of the subframe and floor

• Dedicated models: Audi A7 Sportback / S7 / RS7 (4K8 body type) and Audi A6 / Avant / Allroad (4K / C8 type)

• Steering side: Left (LHD) and Right (RHD) – symmetrical component

• Condition: Original used part (100% functional – profile perfectly straight, factory geometry intact, no post-collision bends, mounting holes round and un-ovalized, no dents or cracks)

• Manufacturer: Audi AG / VAG (Original OEM)

Main application:

• Audi:

  • A7 Sportback (4K8 type) – model years 2018 to 2026 (all engine versions and Quattro / FWD drives)

  • S7 Sportback (4K8 type) – model years 2019 to 2026

  • RS7 Sportback (4K8 type) – model years 2019 to 2026

  • A6 / A6 Avant / Allroad (4K2 / 4K5 / 4KA - C8 type) – model years 2018 to 2026

  • S6 / RS6 Avant (4K - C8 type) – model years 2019 to 2026

Fitment guarantee and VIN verification

Each support undergoes a mounting surface geometry check to ensure there is no warping, and is cleaned before shipping.

Fitment / installation note: Base part number 4K0 803 145 (body group 803) is a key component for the torsional rigidity of the front section of the C8/4K platform floor pan. Even minimal warping of this support after a bottom impact or collision can cause difficulties with correctly setting the suspension geometry, rubbing against the lower engine covers, or transferring vibrations to the bodywork. The original OEM support guarantees a perfect fit for the factory frame bolt holes without the need for stretching. Before purchasing, we recommend comparing the OE number stamped on the part profile or verifying fitment using the vehicle's VIN.