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BBK Long Tube Header O2 Extensions and Hardware Kit (15-17 GT)

Item 389761
Market Price $79.09 You Save 12% ($9.10)
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    Features, Video & Details

    • BBK O2 Extension and Hardware Kit
    • Required for Installation of Long Tube Headers
    • Includes Two 6-Pin Harnesses and Five Bolts
    • Fits 2015-2017 5.0L GT Mustangs

    Review & Installation Video

    Review & Install Video

    The BBK Long Tube Header O2 Extensions and Hardware Kit is available for any 2015 or newer Mustang GT owner who has or is looking to upgrade to a set of long tube headers and wants to extend their O2 sensor harness to the bongs on the tubes in order to plug them into the sensors. The installation is literally as easy as plugging them in, which is why I'm giving it one out three wrenches on our difficulty meter. The O2 sensor harness on the S550s are just a little too short to reach the new bongs on the set of long tube headers, so the extensions will make up for that length. The quick plug-and-play style connectors have six pin harnesses and five bolts that will help get these installed and ready to go. They clip right into the factory harness on one end, then into the back of the 02 sensors, and your long tubes on the other. They're specifically used for upstream sensors, since these are the ones that are need correcting. Without these, you'll be left with useless 02s, which, of course, is not exactly street legal in most areas, and of course, will help make the exhaust gases not flow as properly, which can then lead to a poor engine performance. They have a sleeve lining on the wiring that gives them a layer of heat protection from the exhaust metal, which extends their lifetime and makes them a little bit more durable to withstand the elements. The kit comes with two extensions, one for each side of the exhaust, and will run at about 60 bucks for what you see here, which, again, is necessary if you want those O2s plugged in properly. The plug-and-play harness eliminates any need to splice in or fabricate your own set, which a lot of guys would have to do otherwise, so for the price, you're definitely making your life a lot easier, in my opinion. The installation comes with the bolts necessary to get the job done, like I said, and it really shouldn't take too long to tackle. I'd say, about 30 minutes to an hour in the driveway at home, if that. You wanna have a very basic ratchet and socket set, as well as a jack stand and jacks to safely secure the car, of course. Giving this one out of three wrenches on our difficulty meter. Now, you wanna be able to jack the car up, support the weight, plug the extensions into the factory harness in the O2s, on the long tube headers, and secure the wiring back. Obviously, plug the other end in, and you're good to go. Obviously, not too hard to tackle in your driveway at home. Just to wrap things up, if you're the owner of a 2015 or newer Mustang GT with long tube headers, you might wanna check out the BBK Long Tube Header O2 Extensions and Hardware Kit, which is available right here at

    Required For BBK Long Tube Headers. When installing a set of BBK long tube headers on your Coyote powered S550 Mustang the factory front oxygen sensor wire harnesses come up short and won't reach the upstream O2 sensors. That is why you will need a BBK Performance O2 Extension and Hardware Kit to bridge the gap allowing you to reconnect your sensors in an easy plug-n-play fashion.

    Application. This BBK Performance O2 Extension and Hardware Kit is designed to extend the front (upstream) O2 sensor harnesses on the 2015 to 2017 GT Mustang models.

    Please Note. O2 Sensors are not included with this Extension and Hardware Kit.

    Fitment: 2015 2016 2017 Details

    MPN# 16332

    CA Residents: WARNING: Cancer and Reproductive Harm -

    What's in the Box
    • (2) O2 Harness Extenders
    • (5) Bolts
    Installation Info
    Tech Specs
    Will it fit my Mustang?

      Customer Photos (3) Submit Your Photo

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        Questions & Answers (3)

        3 Top Rated Questions

        Will these work with Kooks Long Tube Headers?

        Bought bbk long tube headers for my 15 s550 5.0, but the harness extensions are for the year 2011-2014 i guess that was a mistake?

        Will the work for the Pypes Long Tube headers?

        • The O2 sensor extensions included in the BBK Long Tube Header O2 Extensions and Hardware Kit would be compatible.

        Helpful (0)
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          Customer Reviews (23) Write a Review

          Ratings Summary

          4.7 out of 5 overall rating from 23 customers

          Installation Time: Afternoon

          Installation Cost: $100-$250

          • July 28, 2019

            5 2017 GT - COgle Installation Time: Less than 1 Hour

            The Perfect Adaptors

            When changing O2 sensors, these adaptors are perfect for the BBK Long Tubes.

            Helpful (0)
          • June 20, 2019

            3 2016 GT - Drese

            The hardware kit comes up short

            The extensions work perfect. As far as the hardware goes, this kit doesn’t even provide half the header bolts. I had to go to two 3 different part stores to obtain enough.

            Helpful (0)
          • May 21, 2019

            5 2015 GT - Swyland Installation Time: Less than 1 Hour

            2015 fbo mustang gt

            needed extensions for the long tubes. Plug and play. Would recommend

            Helpful (0)
          • May 05, 2019

            5 2015 GT - Rickye Installation Time: Less than 1 Hour

            Life Saver

            So I actually purchased a set of longtube headers for my car the set came with Everything needed for the install but unfortunately one of the o2 extensions that came with my headers wasnt grounding so there for was giving me a bad misfire I called American muscle they told me that in order for them to send me a replacement pair I was going to have to send a shop report starting that was the problem it that it may take a few days wich I had no time to wait since i daily my car then i asked for other options and book bbk came in clutch really good quality way better than what originally came with my headers worth every penny and that fixed my horrible misfire!

            Helpful (0)
          • June 18, 2018

            5 2015 GT - Mystang07gt Installation Time: Less than 1 Hour

            Made my life easy

            East plug and play installation. Perfect length for what I needed them for.

            Helpful (5)
          • May 14, 2018

            4 2016 GT - Andrew3 Installation Time: Less than 1 Hour


            Pretty pricey for the only needing to use one of the extensions. Good overall. Plug in and play style harness.

            Helpful (5)
          • February 02, 2018

            5 2016 GT - KF Installation Time: Less than 1 Hour

            Worked perfect

            Very simple just plugs right in. The length was almost spot on. Zip tied the excess so it didn’t hang. Doesn’t get any easier than that.

            Helpful (4)
          • January 26, 2018

            5 2015 GT - MichaelB Installation Time: Less than 1 Hour

            BBK Long Tube O2 Extensions

            Perfect fit. Ordered with Long Tubes and H/F Cats.

            Helpful (5)
          • December 22, 2017

            5 2017 GT - DrewF Installation Time: Less than 1 Hour

            Good product

            Good product, nice fit, zero problems . Would recommend

            Helpful (4)
          • October 15, 2017

            1 2015 GT - BritishM

            Only had One extension harness

            I brought the extension harness along with my headers but didn’t need them because they came with the headers. Then both sets were the back extenders. They didn’t have the front in neither one of the boxes.

            Helpful (5)
          • October 05, 2017

            5 2015 GT - Major Installation Time: Less than 1 Hour


            They are great. They really opened up the sound of my exhaust. The only thing is I brought the extension and they didn’t have the front extension in the box. I wonder will they send me one or give me my money back

            Helpful (5)
          • September 25, 2017

            5 2017 GT - Racerx Installation Time: Shop Install


            Fit perfectly no problem with length or connections

            Helpful (5)
          • September 04, 2017

            5 2016 GT - Bruno3112 Installation Time: Less than 1 Hour

            2016 GT, BBK LTH Install

            The headers I received had extensions with them in the the hardware box. I don't know what year mustang they are for but they didn't fit any of my 02 connectors. These extensions did fit on my 02 connectors. The front 02 wire harnesses don't reach with the LTH, but these fix that problem. They leave a decent amount of excess wire hanging so you will need something like heavy duty zip ties to retain the excess.

            Helpful (7)
          • July 22, 2017

            5 2017 GT - Tony Installation Time: Shop Install Installation Cost: 0-$100

            02 Extensions

            They do exactly what they need to do, and they're easy to move to your liking.

            Helpful (6)
          • July 12, 2017

            5 2015 GT - RaceRed5Oh Installation Time: Less than 1 Hour

            Works well

            After buying long tube headers from AM for my 15 gt and I ordered these being cautious to make sure I had the correct extensions for when I got around to doing the install, luckily for me I needed them cause the headers I got from bbl had the wrong bolts (11-14). I don't like that it only comes with one bag of bolts and only 5 of them in that bag when there's 8 bolts per header, but the connectors and quality seems nice and fitment is perfect. They're about 12" long. I placed a call to AM to see if they can include more bolts with the package considering it says "hardware kit".

            Helpful (6)
          • July 03, 2017

            5 2017 GT - Richard Installation Time: Less than 1 Hour


            They work like they should perfect length and look great no trouble installing easy plung and play

            Helpful (5)
          • June 21, 2017

            5 2017 GT - 17GT Installation Time: Less than 1 Hour

            Works how it should

            Good price for extensions. Worked exactly how they are supposed to and arrived pretty quickly. Quality seems very good

            Helpful (6)
          • May 19, 2017

            5 2015 GT - Ricky Installation Time: Less than 1 Hour

            Did the job

            Was essential do put longtubes on my 2015 mustang gt. Easy plug in play installation, then just zip-tie any slack where ever it fits

            Helpful (6)
          • December 23, 2016

            5 2015 GT - Fidty Installation Time: Shop Install Installation Cost: $250-$500

            They work.

            Bought them had shop install no lights on dash. Ordered these with mid pipe and long tubes.

            Helpful (7)
          • August 26, 2016

            5 2015 GT - Lovelys550

            Great bang for

            This product was exact what I needed to get the job done. I would recommend this product to anyone who has installed long tube headers to their mustang and want to keep their O2 sensors on car.

            Helpful (7)

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