2017-2024 Audi / Porsche Transmission Brace / Sub Frame 4M1399345C

OEM Part #: 4M1-399-345-C (4M1399345C)

$106.72
Used
Donor2017 Audi Q7 · 3.0L
SKU: 551166 · 30-Day Returns
✓ Free Same Day Shipping on orders by noon CT
Only 2 in stock — no guaranteed restock
Transmission Brace / Sub Frame 4M1399345C — Used (SKU 551166)
Genuine OEM Used SKU: 551166 Donor Vehicle: 2017 Audi Q7 · 3.0L 2 photos
$106.72
30-Day Returns
Transmission Brace / Sub Frame 4M1399345C — Used (SKU 505960)
Genuine OEM Used SKU: 505960 Donor Vehicle: 2018 Audi Q7 · 3.0L · 45k miles 2 photos
$106.72
30-Day Returns
  • Genuine OEM — real photos
  • 30-day returns on eligible parts
  • eBay Top Rated · 100,000+ positive ratings
  • Ships from our own indoor warehouse

A used Audi Porsche OEM Transmission Brace / Sub Frame, part number 4M1399345C, removed from a donor vehicle and ready to install. This structural brace stiffens the transmission mounting point and subframe, reducing drivetrain flex. If it becomes cracked or bent, you may notice clunking noises or excessive vibration during acceleration. It fits Audi Q7, Q8, and Porsche Cayenne models with engines including the 2.9L twin-turbo V6, 3.0L turbo V6, and 3.0L PHEV setups.

Specifications

Specifications for Transmission Brace / Sub Frame 4M1399345C
Fits Vehicle ModelCayenne, Q7, Q8
Fits Vehicle MakeAudi, Porsche
OEM Part No4M1-399-345-C (4M1399345C)
CategoryOther

Compatible Vehicles

Fits 68 vehicle configurations across 2 makes, 2017-2024.

Check your specific vehicle before ordering. This list shows year, make, and model. Some years have multiple trims or engines that use different parts, and individual listings may have additional fitment notes (e.g. “with sunroof only”). Review the full variant list below, or message us with your VIN and we’ll confirm the match.

Audi

  • Q7 2017-2020 · 8 variants 8 with notes
  • Q8 2019-2020 · 2 variants 2 with notes

Porsche

View all 68 vehicle configurations — 10 with fitment notes
Full vehicle fitment list for Transmission Brace / Sub Frame 4M1399345C
Year Make Model Trim Engine Note
2023 Porsche Cayenne S Coupe SUV 2.9L V6 Turbo
2022 Porsche Cayenne SUV 3.0L V6 Turbo
2024 Porsche Cayenne SUV 3.0L V6 Turbo
2024 Porsche Cayenne Coupe SUV 3.0L V6 Turbo
2024 Porsche Cayenne S Coupe SUV 4.0L V8 Turbo
2024 Porsche Cayenne S Coupe SUV 3.0L V6 Turbo
2021 Porsche Cayenne GTS Coupe SUV 4.0L V8 Turbo
2024 Porsche Cayenne Turbo SUV 4.0L V8 Turbo
2021 Porsche Cayenne S SUV 2.9L V6 Turbo
2020 Porsche Cayenne S SUV 2.9L V6 Turbo
2021 Porsche Cayenne Turbo S SUV 4.0L V8 Turbo
2021 Porsche Cayenne Turbo Coupe SUV 4.0L V8 Turbo
2024 Porsche Cayenne Turbo GT Coupe SUV 4.0L V8 Turbo
2021 Porsche Cayenne GTS SUV 4.0L V8 Turbo
2023 Porsche Cayenne Turbo S SUV 4.0L V8 Turbo
2023 Porsche Cayenne Coupe SUV 3.0L V6 Turbo
2023 Porsche Cayenne SUV 3.0L V6 Turbo
2023 Porsche Cayenne Turbo GT Coupe SUV 4.0L V8 Turbo
2020 Porsche Cayenne Turbo S Coupe SUV 4.0L V8 Turbo
2020 Porsche Cayenne SUV 3.0L V6 Turbo
2022 Porsche Cayenne S SUV 2.9L V6 Turbo
2019 Porsche Cayenne SUV 3.0L V6 Turbo
2018 Porsche Cayenne SUV 3.6L V6
2018 Porsche Cayenne S SUV 3.6L V6 Turbo
2018 Porsche Cayenne Turbo SUV 4.8L V8 Turbo
2018 Porsche Cayenne GTS SUV 3.6L V6 Turbo
2018 Porsche Cayenne S SUV 3.0L V6 Supercharged
2018 Porsche Cayenne Turbo S SUV 4.8L V8 Turbo
2019 Porsche Cayenne Turbo SUV 4.0L V8 Turbo
2019 Porsche Cayenne S SUV 2.9L V6 Turbo
2020 Porsche Cayenne Coupe SUV 3.0L V6 Turbo
2020 Porsche Cayenne S Coupe SUV 2.9L V6 Turbo
2020 Porsche Cayenne Turbo SUV 4.0L V8 Turbo
2020 Porsche Cayenne Turbo Coupe SUV 4.0L V8 Turbo
2020 Porsche Cayenne Turbo S SUV 4.0L V8 Turbo
2023 Porsche Cayenne Turbo Coupe SUV 4.0L V8 Turbo
2022 Porsche Cayenne S Coupe SUV 2.9L V6 Turbo
2023 Porsche Cayenne S SUV 2.9L V6 Turbo
2021 Porsche Cayenne SUV 3.0L V6 Turbo
2022 Porsche Cayenne Coupe SUV 3.0L V6 Turbo
2021 Porsche Cayenne Turbo S Coupe SUV 4.0L V8 Turbo
2023 Porsche Cayenne GTS SUV 4.0L V8 Turbo
2022 Porsche Cayenne Turbo GT Coupe SUV 4.0L V8 Turbo
2022 Porsche Cayenne Turbo SUV 4.0L V8 Turbo
2021 Porsche Cayenne Turbo SUV 4.0L V8 Turbo
2022 Porsche Cayenne Turbo S Coupe SUV 4.0L V8 Turbo
2023 Porsche Cayenne GTS Coupe SUV 4.0L V8 Turbo
2021 Porsche Cayenne S Coupe SUV 2.9L V6 Turbo
2023 Porsche Cayenne Turbo S Coupe SUV 4.0L V8 Turbo
2021 Porsche Cayenne Coupe SUV 3.0L V6 Turbo
2022 Porsche Cayenne Turbo Coupe SUV 4.0L V8 Turbo
2022 Porsche Cayenne Turbo S SUV 4.0L V8 Turbo
2024 Porsche Cayenne S SUV 4.0L V8 Turbo
2024 Porsche Cayenne S SUV 3.0L V6 Turbo
2022 Porsche Cayenne GTS SUV 4.0L V8 Turbo
2022 Porsche Cayenne GTS Coupe SUV 4.0L V8 Turbo
2023 Porsche Cayenne Turbo SUV 4.0L V8 Turbo
2024 Porsche Cayenne Turbo Coupe SUV 4.0L V8 Turbo
2019 Audi Q8 SUV 3.0L V6 Turbo For Automatic Transmission; For Vehicles With Production date Up To 08/19/19
2020 Audi Q8 SUV 3.0L V6 Turbo For Automatic Transmission; For Vehicles With Production date Up To 08/19/19
2020 Audi Q7 SUV 3.0L V6 Turbo For Automatic Transmission; For Vehicles With Production date Up To 08/19/19
2019 Audi Q7 SUV 3.0L V6 Supercharged For Automatic Transmission; For Vehicles With Production date Up To 08/12/19
2019 Audi Q7 SUV 2.0L l4 Turbo For Automatic Transmission; For Vehicles With Production date Up To 08/12/19
2020 Audi Q7 SUV 2.0L l4 Turbo For Automatic Transmission; For Vehicles With Production date Up To 08/12/19
2017 Audi Q7 SUV 3.0L V6 Supercharged For Automatic Transmission; For Vehicles With Production date Up To 08/12/19
2017 Audi Q7 SUV 2.0L l4 Turbo For Automatic Transmission; For Vehicles With Production date Up To 08/12/19
2018 Audi Q7 SUV 3.0L V6 Supercharged For Automatic Transmission; For Vehicles With Production date Up To 08/12/19
2018 Audi Q7 SUV 2.0L l4 Turbo For Automatic Transmission; For Vehicles With Production date Up To 08/12/19

Ask a parts specialist

Asking about: Transmission Brace / Sub Frame 4M1399345C · OEM #4M1399345C