Rust, noisy or leaking exhaust are common problems, and often the only fix is to replace the muffler. In this article, you will find step by step instruction on how to replace the muffler yourself (without doing any welding). This repair can save you hundreds of dollars.
These pictures are from a muffler replacement on a Nissan Altima, but the instructions apply to many makes including Acura, Ford, Audi, Toyota, Honda, BMW, Lexus, Porche, Chevrolet, etc. You just need to make sure that the muffler you purchase is designed for your particular make, model and year.
Symptoms of a bad muffler
- Loud Exhaust
- Exhaust leak
- Rusted or hole in the muffler
- Deep or loud rumbling sound
- Loud Noise, Deleted or no muffler
- Decreased Mileage MPG
What you will need
To fix your exhaust problems, you will need a few tools and a new muffler.
Instruction on how to replace a muffler
Jack up your car
Use your floor jack to raise up your car. Before you do that ensure the car is in park, and you have set the emergency brakes.
Always use jack stands to support the vehicle. Never get under a car that is supported only by a jack.
- Allow the vehicle cool down for at least a couple of hours before you work on the exhaust.
- You may prefer to disconnect the negative battery terminal as well.
Spray penetrating fluid
Your muffler is held in place with either U-shaped clamps and bolts. You may want to spray penetrating fluid on the bolts and let them soak for at least one hour.
Rusted bolts. Apply some penetrating oil the night before the repair.
Prepare for the worst. Bolts may need to be cut using an angle grinder.
Line up your muffler and pipe
Lay out the new muffler and the pipe.Pay close attention to the gaskets and O-rings that may come with your muffler.
O-ring used to seal leaks at the muffler and pipe flange.
Gaskets installed at the pipe to pipe flange.
Remove the muffler bolts and clamps
This is the most tricky part of this job. Due to high heat, the exhaust bolts can be very hard to remove. Always use the correct size of the socket wrench. Do not use an adjustable wrench on the exhaust bolts, you will most likely strip the bolts. It may be wise to have a spare exhaust clamp and bolts in case your old clamp gets damaged.
Remove old muffler and pipe
Remove the muffler exhaust hangers. These are easy to remove as they typically slide right out. Often some force is required to remove the old muffler.Note that the end of exhaust hanger has a larger diameter and you will need to slide the rubber exhaust hangers over ends. If you end up damaging any of the exhaust hangers or your existing hangers are damaged you can easily find replacement exhaust hangers online.
Once you remove the exhaust clamps and bolts you should be able to slide out the old exhaust. Typically you can pull the old muffler towards the rear of the car. In some cases, you may be able to simply drop the muffler down.
If the old pipes are limiting you from removing the old exhaust you can cut the pipes as long as you have new replacement pipe ready. Some stock mufflers are welded where your new muffler may have clamps and joints, in such case you will have to cut the old pipe in order to remove the muffler.
Always use eye protection and gloves if you have to cut out the old exhaust pipe. Be careful so that you don't get injured. Also, pay attention to any wires or other parts that are near the exhaust. You don't want to accidentally cut anything else.
Install new exhaust
Now you are ready to install the new muffler. Line up the old muffler next to the new one. Make sure you have the orientation of the pipes correctly. Some joints can be tightened before you install the muffler into the car. If you are not sure, don't make any connections yet.
Start installing the new muffler on the car. You may also consider upgrading the muffler at this point. Some car owners choose to delete the muffler and go with a straight pipe instead but that may be illegal in some states.
Use the rubber hangers to secure the muffler in place.
Next, you need to make the pipe connections from the new muffler to the flange on the exhaust system.
Continue by putting together the exhaust pipes. Make sure to install the gaskets when applicable. Some exhaust pipes use an o-ring to at the joints.
Connect the new pipe to the old pipe. Make sure to install the gaskets that came with the muffler.
It is common for aftermarket exhaust systems to come with a sleeve. You will use the sleeve to join the two new pipes together, typically at the middle. You should make this connection last if at all possible. The sleeve is four to five inches long and can be used to make any adjustments when the pipe is too short or the angle didn't match perfectly. It is recommended that you use Muffler and Tailpipe Sealer at joints and connections. The exhaust sealant can help create tight connections. You don't want to have exhaust leaks at joints right after you install a new muffler.
Average cost to replace a muffler
The cost to replace the muffler varies depending on the location and the model of your car. Average prices to replace the muffler range from $300 up to $800 when performing this work at independent repair shops. At the dealership, it can cost over $1000.