Diagnosing Failed Engine Mounts on 2015-2023 Audi A3, S3, TT & VW Golf

Understanding the Mount System in Your Audi or VW

The 2015-2020 Audi A3, 2015-2020 Audi S3, 2016-2023 Audi TT, and 2015-2019 Volkswagen Golf (including Golf R) share a similar engine and chassis design known as the MQB platform. For the 2.0L all-wheel-drive models, the drivetrain is held in place by three key mounts. It's common for owners to replace all three at the same time, as they wear at a similar rate.

• Engine Mount (Passenger Side): This supports the engine's weight on the right side of the vehicle.
• Transmission Mount (Driver Side): This supports the transmission on the left side of the vehicle. This is the part most people mean when they refer to the 'driver side engine mount'.
• Pendulum or 'Dogbone' Mount: This is a lower mount that connects the subframe to the bottom of the transmission. It's primary job is to control the fore-and-aft rocking motion of the engine during acceleration and deceleration.

Symptoms of a Failed Engine Mount

A failing mount will typically make itself known through new noises and vibrations. The most common symptoms include:

• Excessive Vibration at Idle: A noticeable vibration felt in the steering wheel, floor, or seats when the car is stopped in gear.
• Clunking or Thudding Noises: A distinct 'clunk' or 'thump' when you accelerate, decelerate, or shift gears (e.g., from Park to Drive). This is the sound of the engine assembly moving and hitting its limits.
• Rough Start-up and Shutdown: The engine may seem to shudder more than usual when you start it or turn it off.
• Visible Engine Movement: If you have a helper put the car in gear, hold the brake, and gently apply the throttle, you may see the engine lift or rock significantly more than an inch.

How to Diagnose a Bad Mount

You can often diagnose a bad mount with a few simple checks:

1. Visual Inspection: Look at the rubber portions of the upper engine and transmission mounts. Look for deep cracks, tearing, or separation of the rubber. These mounts are hydraulic, so look for dark, oily residue around the mount, which indicates the internal fluid has leaked out. A collapsed mount will have a much smaller gap between the metal housing and the vehicle's frame compared to a new one.
2. Brake-Torque Test: With the hood open, have a helper sit in the car, hold the brake pedal firmly, and shift into Drive. When they briefly and gently apply the gas, watch the engine. If it lifts up violently, a mount is likely bad. Do the same in Reverse. Excessive movement in Drive often points to the passenger-side or lower mount, while movement in Reverse can point to the driver-side mount.
3. Pry Bar Test: For the lower dogbone mount, you can use a pry bar to check for play in the rubber bushings. There should be very little movement. For the upper mounts, you can carefully use a floor jack and a block of wood under the oil pan or transmission to slightly lift the engine. If the cabin vibration disappears as you take the weight off the mount, the mount has failed internally.

Known Issues, TSBs, and Recalls

As of early 2026, there are no specific recalls or Technical Service Bulletins (TSBs) issued by Audi or Volkswagen directly addressing premature failure of the engine, transmission, or dogbone mounts on these models. Failures are typically due to age, mileage, and wear. However, several other recalls exist for these vehicles for issues like fuel pumps and rear springs, so it's always wise to check your VIN on the NHTSA website.

Buying a Used Engine Mount: What to Check

A low-mileage used OEM mount can be a smart purchase, often providing better performance and longevity than a cheap aftermarket alternative. The rubber compounds used by the original manufacturer are specifically designed for the vibration profile of your engine. Aftermarket parts can sometimes be too hard, leading to increased cabin vibration.

When inspecting a used mount, look for these red flags:

• Cracks or Tears: Flex the rubber by hand. Any visible cracks, splits, or tearing in the rubber means the part is no good.
• Fluid Leaks: Check for any signs of oily residue. A dirty or stained appearance around the rubber bellows indicates the hydraulic fluid has leaked out, and the mount's damping ability is gone.
• Sagging or Collapse: Compare the used mount to a picture of a new one. If the rubber part looks compressed or 'pancaked', it has failed and will not support the engine correctly.
• Corrosion or Damage: Inspect the aluminum or steel housing for any cracks, heavy corrosion, or stripped bolt threads.

For these vehicles, a used mount with under 60,000 miles that passes a thorough visual inspection is generally a safe and cost-effective option.

Replacement Overview and Difficulty

Replacing the mounts on these vehicles requires supporting the engine's weight. This is a critical safety step. Never attempt to remove a mount without a floor jack or engine support bar holding the drivetrain in place.

Transmission Mount (Driver Side)

• Difficulty: 3/5 (Moderate)
• Time: 2-3 hours
• Details: Access requires removing the airbox, battery, and battery tray. Once cleared, the bolts holding the mount to the chassis and transmission can be removed. The engine must be supported from below.
🎬 See this step-by-step transmission mount replacement walkthrough.

Engine Mount (Passenger Side)

• Difficulty: 3/5 (Moderate)
• Time: 1.5-2.5 hours
• Details: Access is easier than the driver's side. The coolant reservoir must be unbolted and moved aside. With the engine supported, the mount bolts can be accessed and the mount can be swapped.

Pendulum 'Dogbone' Mount (Lower)

• Difficulty: 1/5 (Easy)
• Time: 30-60 minutes
• Details: This is the simplest of the three. It is easily accessible from under the front of the car. Simply remove two or three large bolts, swap the mount, and reinstall the new bolts. The engine does not need to be supported for this procedure.

Cost Comparison for Drivetrain Mounts

Prices can vary by location and supplier. The following table provides an estimated cost breakdown for each of the three main mounts.

Frequently Asked Questions (FAQ)