How much does a muffler installation cost?

Being that yours is a 2007, there shouldn't be any trouble (or very little) at removing the muffler yourself, and saving money in the process. All you need is some P.B. Blaster (incase the muffler clamps are a bit stubberon), A breaker bar, rachet, and the proper size wrenches and or sockets. Like I said, being that your car is that new,things should come appart decently. I see no reason why you couldn'r do the job yourself. As to the cost of taking it to the repair shop, well every shop is different. So every price will vary as well. I am guessing though that the price would at least be from $300 to possibly even $600, cause they like to screw around and wast some time in the process.  more

Every place is different with their rates and estimated times. I have an 06 gt. I did my complete exhaust by myself. O/r h and frpp stinger axlebacks. You do not need to put car up on jackstands. I can easily slide my arm underneath the car just sitting in the garage. It's best just to back up on a board for leverage and set parking brake, other boards to chalk tires in place just for safety. It is very simple and I have changed mine out many times. You just have one clamp to get off, holding the beginning of the muffler and two hanger brackets. That's all. 13 or 15mm for the hangers(forgot off the top of my head) a little penetrant for the clamp is also needed.  more