Hey guys! Just finished installing the Gibson Performance Exhaust Cat-Back System for my 2007 Navigator. This kit can be found here. I figured I'd do a little write up on the whole process since this isn't something that people usually do. Maybe it'll help somebody out. Here ya go:

Step 1:
Remove the spare tire from the rear.


Step 2:
Remove the spare tire splash guard. This will make it much easier to work with later.


Step 3:
Time to remove the nasty old glass-pack. While it sounded mean sometimes, definitely not my best decision. Just remove the two bolts from the flange and it should fall off.


Sidenote:
Here's a look at the pipe coming back from the catalytic converters once you've removed your factory exhaust.


Sidenote:
Here's another look at the nasty glass-pack. It's funny because my exhaust must have gotten so hot at some point that it actually burnt the red powder-coat paint right off. You can also see where we welded part of the factory flange to the glass pack.


Step 4:
Time to get the first piece of the kit installed. This is the piece of pipe that actually connects to the factory cat-pipe and flange. It just bolts right up with the supplied nuts and bolts.


Sidenote:
The nuts and bolts actually came with a set of lock washers and a flat washer to go on the factory side of the flange, but I couldn't make them all fit for the life of me, so I just left them off.


Step 5:
Connecting the new Gibson muffler to the flange pipe. This is done using their supplied clamps. It's definitely worth noting, DO NOT TIGHTEN CLAMPS UNTIL EVERYTHING IS IN PLACE. I actually made this mistake, and I believe my tip sits a bit odd because of it, but there's not much I can do now. Also worth noting you can use a jack stand to support the muffler once you get it in place.


Step 6:
Now you need to connect the piece of pipe that goes over the suspension to the other side of the muffler. Gibson provides a piece of extension pipe for ford's "L" vehicles. This was obviously not needed in my case.


Sidenote:
You can see here that this is one of the problems you may encounter if you start to tighten your clamps before getting everything perfectly in place. My factory hanger now doesn't line up with the new one on the pipe and because I had already tightened it, even after loosening the clamp, the pipe was too tight for me to be able to slide it back towards the rear some more to line up with the clamp. This being said, everything seems fairly secure so I'm not too worried about it.


Step 7:
Feed the over-suspension pipe over the suspension. This can be a little tricky, especially if you're like me and aren't doing this on a lift. I actually had ramps under the rear tires, which made this much easier. You definitely need to feed it from the front side of the suspension rather than from the rear. It's also worth noting that you may have to loosen your rear traction bar and let it hang so that you can get the exhaust under there.


Step 8:
Here you'll want to attach the exit pipe. You can see here how mine actually touches my spare tire. I think this has something to do with me tightening everything before getting it in place. I may had been able to move some things around a bit to avoid this.


Step 9:
Finally, slide the exit pipe into the final exhaust hanger. (May be easier to unbolt hanger and slide onto pipe, then rebolt to frame.) Then slide on a bolt on the tip and you're set!


Final Thoughts:
The overall process wasn't too difficult. Definitely need to remember not to tighten the clamps until you have everything in place and everything looks exactly how you want it. The spare tire splash guard didn't have room to go back on so I just left it off, and as you saw, the spare tire now touches the clamp, but I haven't noticed any serious issues or melting yet so I'm going to leave it for now. Sounds muuuuch better and looks muuuuch better. Here's what it looks like! Feel free to ask any questions below.

 

Can you upload a video with how it sounds? Thanks

 

Sorry for the late reply! I've been super busy since getting this installed. I did a short clip on my phone the other day with a cold(ish) start and a quick little rev. Sounds similar to stock at idle and low RPM, but does have a little growl when you get onto it. I'd personally still prefer something with a little more rumble at idle and when I'm on it, so I may swap the muffler out at some point, but I'm very happy with it for the moment. Here's a link to the

 

Thanks for posting, it sounds good to me. Maybe in the future I may do this for my Expedition EL.

 

I have the same system on my 2011 Expedition XLT. Very happy with the system.

 

Sounds really nice! Little $$$$pendy for me tho, although it is stainless and all that. I've been really wanting to do something to mine. May just swap the muffler for something a bit louder....

 

Yeah man, for sure doesn't sound bad. Has just a wee bit more rumble too it than the factory exhaust, plus the tip looks MUCH better. And swapping the muffler alone isn't a bad idea, you just have to be careful because you're gonna have to match the factory pipe and cut just the right amount of pipe off.

 

Yeah well I've been a welder /metal fabricator for only 15 plus years, so none of that scares me lol.

Now if I just knew, among the plethora of muffler options, which one to choose.....

 

Ah okay. If I were you I'd go with either the Flowmaster Super 50 or Flowmaster 40 muffler.

 

Yeah I'm leaning toward either one of those, or a Magnaflow. I have a Magnaflow on my pickup (06 F150 5.4) and like it pretty well. We are planning a 2500+ mile trip this summer in the Expy and I DO NOT want drone! I just want a free-er flowing muffler to maybe help out the fuel economy just a bit, and be able to hear the V8 when I stand on it.

 

Well, after some more research and head-scratching, I ordered a Summit Racing brand stainless muffler. Basically the same design as a magnaflow, at half price or less. The reviews on Summit's website were all positive, so hopefully it'll be a good product. We shall see. Supposed to get here Tuesday, and hopefully I can find time to install soon afterward.