How to replace your mk4 golf/gti/jetta subframe AKA Crossmember Season 2

Introduction

In this tutorial, we'll guide you through the process of replacing the subframe (also known as the crossmember) on a Mk4 Golf, GTI, or Jetta. This is a crucial repair if your subframe is damaged, as it can lead to alignment issues and vibrations while driving. We’ll cover the necessary tools, step-by-step instructions, and tips to ensure a successful replacement.

Step 1: Gather Your Tools

Before starting the replacement, make sure you have the following tools ready:

• 16mm, 13mm, 21mm, and 18mm sockets and wrenches
• Jack stands
• Jack
• Approximately 10 feet of rope or a bungee cord for support

Step 2: Prepare the Vehicle

1. Lift the car using jack stands to ensure a safe working environment.
2. Support the steering rack by wrapping a rope around the bottom. This prevents it from sagging when the subframe is removed.

Step 3: Remove the Control Arms

1. Detach the ball joint:
   • Remove three 13mm bolts from the control arm.
   • Use a wrench to hold the top nut while removing the two 18mm bolts.
2. Pull the control arm down and out of the socket. Repeat this process for the other side.
3. Tip: Be cautious not to pull on the axle too much, as this can dislodge it from its socket.

Step 4: Remove Supporting Components

1. Remove the dog bone mount:
   • Use a 16mm and a 13mm socket to unbolt it. Expect the engine to swing back slightly, but this is normal.
2. Unbolt the power steering rack:
   • Remove the two 13mm bolts securing the steering rack to the subframe.

Step 5: Remove the Subframe Bolts

1. Unfasten the subframe bolts:
   • Use a 21mm socket to break loose the four subframe bolts. A breaker bar may be necessary due to tightness.
2. Leave a few threads on the bolts before removing them completely to prevent the subframe from dropping suddenly.

Step 6: Support and Remove the Subframe

1. Once the bolts are mostly removed, support the subframe with your hands.
2. Gently lower the subframe while ensuring the steering rack is still supported by the rope.
3. Slide the subframe out of the vehicle once it is free from all attachments.

Step 7: Install New Bushings

1. If you’re replacing the bushings, press them out using a press or a suitable tool.
2. Insert new bushings into the new subframe. If you encounter difficulty, apply some lubrication to ease the process.

Step 8: Reinstall the New Subframe

1. Position the new subframe in place. Get assistance if necessary.
2. Thread the subframe bolts by hand to prevent stripping.
3. Install the steering rack bolts next, ensuring they align properly.
4. Torque all bolts to the manufacturer's specifications once everything is in place.

Step 9: Reassemble Components

1. Reattach the dog bone mount and control arms, reversing the disassembly steps.
2. Ensure all bolts are tightened to the correct specification.

Step 10: Final Checks

• Once everything is back in place, double-check all connections and ensure nothing is loose.
• Important: You will need to have your vehicle aligned after this procedure as removing the subframe can throw off the alignment.

Conclusion

Replacing the subframe on a Mk4 Golf, GTI, or Jetta is a manageable task with the right tools and steps. Remember to take your time, support components as needed, and pay attention to the alignment afterward. Happy wrenching!