Digitalgp
Elite Explorer
- Joined
- February 13, 2018
- Messages
- 224
- Reaction score
- 53
- City, State
- Hudson valley
- Year, Model & Trim Level
- ‘15 XLT
This swap began because my factory mufflers were in rough shape. The metal must be very thin on these as they were literally splitting at all the seams. Even found they were rotting through on the top side... especially the passenger one as you can see in my picture. I used some muffler putty and after it set I wrapped the mufflers up in high temperature flue tape since that was all I had at my disposal. Anyone experiencing exhaust odor after hard acceleration I highly suggest you check over your mufflers and flex pipes. There is a good chance the tops of your mufflers are starting to rot through. I started experiencing this odor which I swore was coming from under the hood...I was wrong. Must be something with the way air drafts from underneath the vehicle. After this swap the hard acceleration odor I started getting is completely gone. I tried to include as many pictures as I could in this writeup. Keep in mind this was done on my 2015 XLT.
Back to the main subject. The swap over to the true dual exhaust on the 3.7 piu isn’t quite as straight forward as it may seem, but no major hurdles. The obvious stuff is everything behind the manifolds has to get swapped out. The new front pipe and catback will physically bolt up and fit, however I found the hangers to be different in a few spots. Behind the flex section the factory xlt exhaust has 1 hanger on the passenger side. The 3.7 piu exhaust has one on either side. Of course with my luck the hanger to the passenger side came off when trying to remove the broken flex pipe off the doner exhaust. I had to get some help to have it welded back on. I also had to rig a hanger for the driver side as the hanger only comes as part of a cross brace from Ford that comes on the PIU’s which runs over $100. Right now it consists of a ‘20 escape rear muffler hanger zip tied into the frame and a spare rubber insulator I had from my ‘12 Fusion.
The xlt exhaust has a hanger that mounts on the drivers front side of the rear crossmember. This is still used with the the 3.7 piu catback, however it has additional hangers on both sides on the back of the rear crossmember. Easy enough to fix. I got together the hangers and hardware to add into the rear subframe which is two hangers, 4 bolts and 4 c-clips. The clips just go right into the rear subframe. The openings are already there. For some reason the bolts are more money for the explorer PIU than the Flex ecoboost which uses the same size bolts under a different part number. The clips are the same in both applications.
Other than what I have mentioned everything else went smoothly. I opted to cut off the turn downs and use ap exhaust ST1257S exhaust tips which are meant for the ram 1500 which I think look right at home on here. I also had to purchase additional exhaust adapters and clamps from the local Napa for this.
Maybe to answer a few other questions about the swap...
What does the resonator on the 3.7 catback look like inside? Maybe nobody else is asking this, but I was very curious myself. From what I was able to tell it’s a hollow case with two straight perforated pipes running parallel to each other inside. Maybe down the road I will consider changing this out for an H-pipe or X-pipe, but that’s for another time and not sure if there would be any kind of advantage to doing that. I would think the resonator already acts as some kind of balance pipe.
Was there any performance gains? Hard to say. I don’t have access to a dyno, but after driving it with the new exhaust it definitely has better pickup and a lot more responsiveness. This in conjunction with my k&n drop-in and psudo-ram air intake (which I pictured in another thread) I would like to think I gained a little something, but then again the mufflers on my old exhaust were so f-d up that maybe I was being robbed of power. It’s also back to being super quiet again. As far as gas mileage not a huge difference. Maybe .5-1.5 mpg tops with my usual driving. I have not taken it on a long enough highway trip to know if it made a difference there because I take the Fusion to save on gas for those trips.
Was it worth the swap? Yes in the sense of having a functional exhaust again and bragging rights for having true duals. Also for those like me who just don't like the factory y-pipe. No in the sense of if your looking for real gains in performance or gas mileage to the cost...I would imagine similar results to doing an aftermarket catback exhaust without noise. The catback didn't cost me anything, but I did have to pay for the front pipe and some hardware.
All in all I am happy with the swap and to have something a little different. Hope this provided some useful information to anyone curious.
Back to the main subject. The swap over to the true dual exhaust on the 3.7 piu isn’t quite as straight forward as it may seem, but no major hurdles. The obvious stuff is everything behind the manifolds has to get swapped out. The new front pipe and catback will physically bolt up and fit, however I found the hangers to be different in a few spots. Behind the flex section the factory xlt exhaust has 1 hanger on the passenger side. The 3.7 piu exhaust has one on either side. Of course with my luck the hanger to the passenger side came off when trying to remove the broken flex pipe off the doner exhaust. I had to get some help to have it welded back on. I also had to rig a hanger for the driver side as the hanger only comes as part of a cross brace from Ford that comes on the PIU’s which runs over $100. Right now it consists of a ‘20 escape rear muffler hanger zip tied into the frame and a spare rubber insulator I had from my ‘12 Fusion.
The xlt exhaust has a hanger that mounts on the drivers front side of the rear crossmember. This is still used with the the 3.7 piu catback, however it has additional hangers on both sides on the back of the rear crossmember. Easy enough to fix. I got together the hangers and hardware to add into the rear subframe which is two hangers, 4 bolts and 4 c-clips. The clips just go right into the rear subframe. The openings are already there. For some reason the bolts are more money for the explorer PIU than the Flex ecoboost which uses the same size bolts under a different part number. The clips are the same in both applications.
Other than what I have mentioned everything else went smoothly. I opted to cut off the turn downs and use ap exhaust ST1257S exhaust tips which are meant for the ram 1500 which I think look right at home on here. I also had to purchase additional exhaust adapters and clamps from the local Napa for this.
Maybe to answer a few other questions about the swap...
What does the resonator on the 3.7 catback look like inside? Maybe nobody else is asking this, but I was very curious myself. From what I was able to tell it’s a hollow case with two straight perforated pipes running parallel to each other inside. Maybe down the road I will consider changing this out for an H-pipe or X-pipe, but that’s for another time and not sure if there would be any kind of advantage to doing that. I would think the resonator already acts as some kind of balance pipe.
Was there any performance gains? Hard to say. I don’t have access to a dyno, but after driving it with the new exhaust it definitely has better pickup and a lot more responsiveness. This in conjunction with my k&n drop-in and psudo-ram air intake (which I pictured in another thread) I would like to think I gained a little something, but then again the mufflers on my old exhaust were so f-d up that maybe I was being robbed of power. It’s also back to being super quiet again. As far as gas mileage not a huge difference. Maybe .5-1.5 mpg tops with my usual driving. I have not taken it on a long enough highway trip to know if it made a difference there because I take the Fusion to save on gas for those trips.
Was it worth the swap? Yes in the sense of having a functional exhaust again and bragging rights for having true duals. Also for those like me who just don't like the factory y-pipe. No in the sense of if your looking for real gains in performance or gas mileage to the cost...I would imagine similar results to doing an aftermarket catback exhaust without noise. The catback didn't cost me anything, but I did have to pay for the front pipe and some hardware.
All in all I am happy with the swap and to have something a little different. Hope this provided some useful information to anyone curious.
