Changing the Exhaust on Your Car or Truck (DIY)

A damaged exhaust system lets waste gases from the car engine escape before the gases reach the rear of the car. The leaked gas makes a noise that gradually gets louder as the cracks or holes on the exhaust get bigger.

Tools you might need during the procedure:

  • Large screwdriver
  • Hammer
  • Spanners
  • Sockets
  • Wire brush
  • Jack
  • Emery cloth
  • Cold chisel
  • Engine oil
  • Torch
  • Goggles
  • Gaskets
  • Ramps

Before removing the old exhaust, try to sketch the layout properly noting where it is fixed in relation to the suspension and handbrake linkage. You should also note how rubber hangers are fitted because if you assemble incorrectly, excessive movements in the system will occur which can shorten its lifespan.

To undo the manifold joint, try to raise the car on axle stands or ramps securely. In most cases, the nuts are badly corroded making it difficult to undo. So, you should clean the visible threads with a wire brush and lubricate with penetrating oil. Use a ring spanner or sockets to undo the joints. After removing the joint, remove the old exhaust pipe and use a scraper to clean the traces of gasket on the manifold.

To reconnect the manifold clamp and flange joint, firstly clean the clamp of the fire-resistant compounds using a wire brush and then lubricate the bolts until you can tighten the bolts with your hand. Coat the metal-to-metal joints with a fire-resistant compound. Ask someone else to jack the pipe into position for you as you arrange the clamps around it.

Add the washers and other fittings; screw the nuts with your hand and tighten (lightly) with a spanner. Do not tighten fully until the system has been completely fitted.

Clean the threads on the studs of the flange joint with a wire brush and confirm that the nuts can be screwed easily using a hand. To make the nuts screw easily, the threads should be cleaned and lubricated.

Ensure that the surfaces the gasket will be placed on are clean, and fix the new gasket. Tighten the nuts properly until the flanges are in contact with the gasket (do not compress).

Replace rusted or chafed exhaust mountings. If you are fitting new mountings, cut through the former mounting with a mini hacksaw and ensure you wear goggles.