Replace a Muffler

Like any part of a car, mufflers can eventually wear out or become damaged as you drive your vehicle. Many mufflers are held in place with muffler clamps and rubber hangers, though some may be welded. In either case, you may need to saw the old muffler off of the exhaust piping in order to install a new one. Make sure to follow all of the appropriate safety precautions when jacking up the vehicle or sawing through exhaust piping.

Steps

Removing Your Old Muffler

  1. Park the vehicle on a hard, level surface. In order to access your muffler, you will need to be able to get under the vehicle safely. Choose a location to park your vehicle that is completely flat and firm enough to support the weight of the vehicle on a jack and jack stands. Dirt, grass, or gravel are not acceptable surfaces for this project.
    • Look for a flat area to ensure the vehicle remains stable while being jacked up.
    • Blacktop or concrete are the preferred surfaces to park your vehicle on.
  2. Disconnect the battery. Before starting this project, disconnect the battery by loosening the nut holding the ground cable on the negative terminal using a hand or socket wrench. Slide the cable off of the terminal and tuck it to the side of the battery to ensure it can’t pop up and come into contact with either terminal on the battery.[1]
    • Disconnecting the battery will ensure the vehicle can’t be started while you work on it.
    • The negative terminal can be identified by looking for the letters “NEG” or the negative symbol (-) around the terminal.
  3. Jack the vehicle up and place jack stands beneath it. With the vehicle parked on level ground, place wheel chocks in front of both front wheels. Locate the designated jack points for the rear of your vehicle. If you are unsure where to find the designated jack points, refer to your vehicle’s owner’s manual for guidance. Jack up the vehicle by turning the handle of a scissor jack or by lifting and lowering the jack handle.[1]
    • Once the vehicle is high enough to work beneath, place jack stands beneath the vehicle to support its weight.
    • Never work beneath a vehicle supported only by a jack.
  4. Spray the muffler clamps with penetrating fluid. If your muffler is not welded in place, it will be secured using muffler clamps. Muffler clamps are usually “U” shaped with nuts tightened onto either end. Because the muffler is exposed to road grime and water, it may have accumulated a good deal of rust. Spray a rust penetrator like WD-40 on the bolts and allow it to soak for a few minutes. If the muffler is secured to the exhaust pipe using a flange, the process is the same.[1]
    • You may need to use multiple applications of rust penetrator before you can loosen the bolts.
    • You can purchase rust penetrator at most auto parts or large retail stores.
  5. Use a hand or socket wrench to loosen the nuts on the muffler clamps. With the rust broken loose thanks to the rust penetrator, find a socket or hand wrench of the appropriate size and loosen the nuts on the exhaust clamp. You will probably need to replace the clamp, so if the bolt breaks, it’s okay.[1]
    • If you intend to reuse the muffler clamp, you may want to spray it with more rust penetrator as you work it loose.
    • If you break the muffler clamp, you can purchase replacement clamps at your local auto parts store.
  6. Slide the exhaust and muffler apart. With the exhaust clamp removed, respray the area where the muffler pipe meets the exhaust piping with rust penetrator and allow it to sit for a few more minutes. You should then be able to pull the muffler toward the back of the car to slip the two pipes apart.
    • If the pipes are too rusted together to come apart, you may have to cut the pipes apart.
    • If your muffler was welded in place, you will have to cut the pipes apart.

Cutting Through Rusted Exhaust Components

  1. Put on appropriate safety equipment. Cutting through exhaust piping could free up debris stuck on the bottom of the car and expel metal shavings in the cutting process. As a result, eye protection is absolutely mandatory before moving forward. It is also highly recommended that you wear heavy duty gloves to protect your hands from the blades or sharp pieces of metal left remaining after you make your cut.
    • Goggle style eye protection is best for this type of job. They will prevent debris from falling into your eyes from above, below and on the sides.
    • Leather workman’s gloves can protect your hands from metal slivers and accidental cuts.
  2. Use a cut off tool if available. If you have access to an exhaust cut off tool, it is the best option when removing a welded or rusted on muffler. An exhaust cut off tool goes all the way around the pipe and leaves a cleaner cut than most saws. Wrap the exhaust cutter around the pipe and move the handle back and forth until you cut through the pipe completely.
    • An exhaust cutting tool works in a more confined space that you can often reach with a hacksaw.
    • You can purchase an exhaust cutter at your local auto parts store.
  3. Use a hack saw to cut through the metal just past the clamp. If you do not have access to an exhaust cutter, a simple hack saw will suffice to cut the muffler off of the exhaust pipe. If there is a rusted clamp still in place, cut into the pipe just past the clamp. If there is not, saw through the exhaust piping where it meets with the muffler piping.
    • Make sure to keep your eye protection on throughout this process, otherwise you could get a metal sliver in your eye.
    • Make sure to use a hack saw blade rated for steel. You should not need to use multiple blades to get through the exhaust piping.
  4. Be careful not to cut through anything else. When using a hack saw, the cramped space may make it difficult to saw through the pipe without hitting anything else. Be extremely careful not to saw through any of the lines on the underside of your vehicle, as they may be for your fuel or brakes.
    • Attempt to move anything to the side that interferes with your clearance when sawing through the exhaust piping.
    • You may have to saw through a different portion and purchase more pipe to extend the reach of the new muffler if you can’t saw through the pipe without damaging other things.
  5. Pull the hangers on the muffler off of the rubber muffler mounts. With the muffler no longer attached to the exhaust piping, the only thing holding it in place will be the rubber muffler mounts. The muffler will have a piece of metal extended through a rubber eyelet attached to the body of the vehicle. Pull the muffler out the back of the vehicle to pull the metal portion out of the eyelet.
    • The end of the piece of metal that goes through the eyelet has a larger diameter than the rest, so you will need to pull hard to get it out.
    • If you tear the rubber eyelet, you can purchase a replacement one at most auto parts stores.

Installing a New Muffler

  1. Test fit the new muffler. Take a look at the new muffler next to the old one. Ensure the metal that the muffler hangs from is in the same place and that there is enough piping extended out from the muffler to reach where you disconnected or cut off the previous one. Finally, check the diameter of the piping. The muffler should slide tightly onto the existing exhaust pipe. If it doesn’t, measure the inside and outside diameters of each pipe and purchase an adaptor at your local auto parts store.[2]
    • If the pipe from the muffler doesn’t reach the old pipe or fit, you will need to purchase piping or an adaptor from your local auto parts store.
    • If you use an extension pipe, secure it to the muffler’s pipe in the same manner you would secure the muffler pipe to the exhaust.
  2. Insert the new muffler hangers in the rubber muffler mounts. Slide the metal hanger on the muffler into the rubber eyelet to support the weight of the muffler. The rubber will prevent the muffler from rattling or creating a vibrating noise inside the cabin of the vehicle once the muffler is completely installed.[1]
    • There should still be enough play in the rubber eyelet to allow you to move the muffler around as you secure it to the exhaust piping.
    • Make sure to replace the rubber eyelet if you damaged it removing the old muffler.
  3. Coat the end of the new muffler’s pipe in exhaust sealant. Before sliding the new muffler pipe into place, spray it with an exhaust sealant. Spray on exhaust sealant will help establish an air tight seal between the two pipes and reduce the chances of an exhaust leak where the pipes connect.[1]
    • Depending on the brand, you may need to allow the exhaust sealant to sit for a few minutes before moving on.
    • Refer to the instructions on the exhaust sealant to know how long to let it cure.
    • You can purchase exhaust sealant at your local auto parts store.
  4. Slide the exhaust together. Slide the muffler piping or adaptor over the existing exhaust pipe. The muffler should rest directly below the rubber eyelet, so the eyelet hangs straight up and down. The pipes should fit together snugly. If the two pipes feel loose or can be wiggled, you will need an adaptor to match the correct size.[1]
    • Most exhaust piping comes in two or two-and-a-half-inch diameters.
    • You will not be able to seal the wrong size pipe onto another pipe, even if you overtighten the muffler clamps.
  5. Secure the piping with muffler clamps. With the piping seated properly, slide a muffler clamp over the area where one pipe overlaps the other. Use a hand or socket wrench to tighten the clamp until it is not possible to move the pipes back and forth at all.[1]
    • You may want to use a half inch drive wrench to tighten the clamps to ensure you have enough leverage to tighten it sufficiently.
    • Be sure you tighten the clamp over where the piping overlaps, otherwise you could crush the exhaust piping.
  6. Start the engine to check for leaks. Ensure vehicles equipped with automatic transmissions are in park and those with standard transmissions are in neutral with the front wheels securely chocked. Start the car and look beneath it at where the muffler and exhaust piping meet. An exhaust leak would likely be visible if there is one.[1]
    • If you are unsure about whether there may be a leak, ask a friend to press down on the gas pedal slightly to increase the RPMs of the engine. This will make leaks more apparent.
    • If you identify a leak, allow the piping to cool off and try to assess its cause. You may need to remove the muffler clamp and seat the two pipes together properly before re-tightening the clamp.

Related Articles

Sources and Citations

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 http://www.autoanything.com/articles/how-to-change-your-muffler.aspx
  2. ↑ http://www.apidaonline.com/index.php/guides/item/how-to-replace-a-muffler
Retrieved from "https://kipkis.com/index.php?title=Replace_a_Muffler&oldid=320695"