My 2005 stock mustang had a really nice sounding exhaust from the factory but it is missing that deep growl that sets it apart from rest of the crowd. That is why I decided to go with a Mac Performance axle back exhaust so I can feel the power and people can notice that a mustang is passing by.
First things first, use a ramp or jackstands to lift the rear end of the car. Now get under there and check all the locations of the hangers and the clamps. You will be un-bolting the hangers and the clamp for each muffler.
Lets start by doing one side first. Loosen the muffler clamp, the muffler clamp is attached / welded to the factory muffler pipe and will stay on the muffler itself. You need it completely loose so you can slide it off. Just loosen the bolt until it’s almost out. You can push the muffler and notice it slide when it’s loose.
There are 4 smaller bolts that hold the hangers in place and the one larger one at the muffler clamp, they all need to be removed.
To get the bolts loose, just take your time and use a small wrench to access the hanger bolts that are hard to get to. Unfortunately with the stock muffler, all you can fit in there is a smaller wrench. Fortunately, that’s all you need to break it loose.
Carefully loosen all the bolts, you can almost do the whole thing by “feel” once you get going on loosening the bolts.
Now drop down the stock muffler system. it will come down easy and maybe stick a little at the muffler clamp. Twist it and pull it down and to the back and it will pop off.
After the factory muffler is down DON’T TOUCH IT. First take careful note of the orientation of the hangers. You are going to transfer the hangers from the old muffler to the new Mac muffler. The new mac system is smaller, making it much easier to bolt into place.
Just slip the hangers onto the new system and also slip the new supplied muffler CLAMP over the end of the open pipe before you raise the new muffler into place.
Next lift the Mac muffler into place by FIRST sliding it on the pipe, then bolting the hangers into place. You can tighten all the muffler HANGERS at this time but keep the muffler clamp at the rear LOOSE.
Here is the muffler clamp, what you want to do is slide the new muffler so that it’s right up against the notch. But no need to worry if it’s not 100% against it or if you notice it slip as you tighten the clamp. Just make sure it’s close. If you notice it slip down quite a bit, you may need to loosen and slide it up and hold it in place “as” you tighten.
Once the muffler is in place. Get out and look at your Mustang from the rear, compare the muffler position to the stock muffler and hang the muffler nice and flat. You may need to loosen and twist / hold the muffler as you tighten it. Just get the system as flat as you can.
The muffler clamp is the only place where you can adjust the look / hang of the system. When you are happy with the looks, then tighten the clamp down completely.
A total install can be done in 20 minutes. Again we love the Mac system and have always liked the price / performance of the Mac mufflers. They sound nice and deep, and for people like us, it’s the perfect sound.
