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Ford Performance 3.73 Gears and BAMA X4 Tuner (99-04 V8)

Market Price $699.99 You Save 11% ($80.00)
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$619.99

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  • Item 101657

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Ship to: Ashburn - 20149
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    Features & Details

    • Money Saving Combo Kit
    • Bama SF4/X4 Tuner with 3 Custom Tunes
    • Free Tunes for Life
    • Ford Racing 3.73 Gears - 8.8"
    • Motive Gears 8.8" Rear End Installation and Bearing Kit
    • 2 Quarts Royal Purple Max Gear 75w90 Gear Oil
    • 1 Quart of Ford Racing Friction Modifier
    • Includes datalog reviews to ensure your vehicle is fully optimized
    • Fits 1999-2004 V8 Mustangs
    Bama Performance

    The Gears
    The Gears

    Improve ET's and Low End Torque. Installing a set of steeper rear gears is a great way to get more low end grunt off the line and lower your ET's at the same time. Ford Racing Mustang ring and pinion gears feature a super strong forged construction, CNC cut & lapped gear teeth, and a black oxide finish to resist corrosion making them perfect for street, road, or race use. More info about these gears - Here

    The Tuner
    The Tuner

    Power. Performance. Personalized. The SCT Power Flash Tuner features Bama Performance custom tunes that are written specifically for your Mustang. Our tunes are based on a 19 point questionnaire to deliver the most power and performance possible for your Mustang’s modifications. All Bama Performance tunes are tested and proven on our very own in-house Dynojet 224xLC Chassis Dyno. More info about this tuner - Here

    The Combo
    The Combo
    • More horsepower and torque
    • Better throttle response
    • Enhances existing modifications
    • Custom Dyno proven tunes
    • Free Tunes for Life


    Technical Note. Installation costs will vary, but a good rule of thumb is between $250 and $300. Be sure to work with a reliable shop that you trust for installations. You can also save money on your installation labor by having your Trac-Lok rebuilt at the same time as your gears are installed, see drop down option above.

    **NOTE: Programming custom tunes may take 2-3 business days plus applicable shipping time. We recommend ordering other products separately to avoid delay. Some heavily modified cars are not tunable with a mail order tune. Click for details. Membership in the Tunes for Life program is is valid for as long as you own the car that was originally tuned and is non-transferrable.

    Fitment: 1999 2000 2001 2002 2003 2004 Details

    CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

    What's in the Box
    • (1) SF4/X4 Power Flash Tuner
    • (1) One USB PC Interface Cable
    • Ford Racing 3.73 Gears
    • Motive Gears 8.8" Rear End Installation and Bearing Kit
    • (2) quarts Royal Purple Max Gear 75w90 Gear Oil
    • 1 quart of Ford Racing Friction Modifier
    • Free Tunes For Life
    Installation Info
    Tech Specs
    Bama Custom Tuning at AmericanMuscle. Power. Performance. Personalized. Proven
    Ordering a Custom Tune?Whether it's a new mod or just an octane change on your existing tunes, our Bama Performance calibrators have got you covered in a few easy steps:
    1. Buy this Tuner & Submit your Mustang's Info
    2. A Bama Performance Calibrator writes custom tunes just for your Mustang & Mods
    3. Load 'em on your Mustang and GO!
    4. As you add new mods, Bama will update your tune files for FREE!
    That's right, Free Tunes for Life!

    More Power. Do you want the ultimate power package for your Mustang? Well look no further, because it has arrived. AmericanMuscle introduces the kit that will launch you into quarter mile times that you have never dreamed of possible; designed to give the best possible performance upgrade for your car, without having to empty your wallet.

    Kit includes: (click on each item for full product description)

    Increased HP and torque. From the factory, the manufacturer programs their vehicles to cater to the needs of the daily driver, not the performance enthusiast. After loading the custom Bama Tune on a vehicle, even a bone stock, unmodified Mustang will realize noticeable gains in HP, Torque, and Fuel Economy.

    Increase your mod's potential. Factory computer settings are calibrated for the original factory components. When making performance modifications, you need to recalibrate the vehicle's computer to realize the full potential that these modifications can achieve.

    Free tunes for life! Every customer that purchases a tuner is enrolled in the "Free tunes for life" program. Any time that you make additional mods to your vehicle, our team of SCT certified Bama Custom Tuners will create new tunes for you.

    Custom Bama Tunes specific to your vehicle. When you order a tuner, you aren't just getting a tuner - you are getting the tuner and 3 dyno-tested custom Bama tunes:

    • Street (87-93 octane) - the street tune is designed as a daily driver program that focuses in on increasing mid-range power. It does give up a few HP at higher RPMs, but that's why there is a Performance file. Automatic vehicles are further enhanced by making adjustments to the transmission's shift points and firmness.
    • Performance (87-93 octane) - The Performance program is designed to add power at 3000 RPMs and higher, focusing more on the top end horsepower and all out performance driving. Timing, fuel and throttle response settings are slightly more aggressive than the street tune. This is a great track tune but also works well for daily drivers that are looking for a little more "get up and go" than the street tune. The automatic transmission settings are the same as in the street tune.
    • Race (91 - 93 octane) - The race tune will ensure the largest increase in vehicle performance. Using the highest grade of fuel available in your area is mandatory. This file is designed for "Race only Use" as the timing, fuel, and throttle response settings are very aggressive. in fact, the adjustments are so aggressive, that we do not recommend it for daily driving as it may cause your vehicle to try to jump out from a stop and easily spin the tires. Finally, with the automatics, we implement entirely new shift points and firmness settings to further enhance the all-out performance of the vehicle.

    Nitrous (91-unleaded race gas) - Our nitrous option can be added to any of our previously mentioned tune options, but only for 91-octane unleaded fuel.

    Easy to load; easy to restore. Not only are the custom tunes easy to load on your vehicle, it is just as easy to restore your factory settings. When you load your custom tune on the vehicle, the tuner automatically stores your vehicle's factory settings. To return the vehicle to its factory settings, just plug the tuner back in, select the option to restore the factory settings, and you're done.

    SCT SF4/X4 Power Flash Tuner Features:

    • The SF4/X4 by SCT is the newest replacement for the popular SF3/X3
    • Reads / Clears DTC Trouble Codes
    • On screen data logging and monitoring
    • Full color LCD display with auto dim feature
    • Built-in WiFi for easy updates
    • PC/Windows compatible
    • Custom tuning applications for 1999-2004 GT, Bullitt, Mach 1 and SVT Cobra Mustangs
    • Click for Instructions on Loading Custom Tunes to your Mustang.

    Approximate RPM for 1999-2004 GT


    Manual
    Gear @25 MPH @35 MPH @45 MPH @55 MPH @65 MPH @75 MPH
    1 3888 5443 6998      
    2 2301 3221 4141 5061 5981 6902
    3 1518 2126 2733 3340 3948 4555
    4 1150 1610 2070 2531 2991 3451
    5 782 1095 1480 1721 2034 2347


    Automatic
    Gear @25 MPH @35 MPH @45 MPH @55 MPH @65 MPH @75 MPH
    1 3267 4573 5880      
    2 1783 2496 3209 3922 4636 5349
    3 1150 1610 2070 2531 2991 3451
    4 805 1127 1449 1771 2093 2416
    Will it fit my Mustang?

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    Questions & Answers (109)

    5 Top Rated Questions

    I have read the contents of this kit, I have watched the video, but I STILL DON'T KNOW if this kit includes the rear gear pinion bearing kit necessary for 2010 Mustang gear swaps? And this is from a person who reads, writes and interprets complex written language for a living... Also, can not find this "drop-down" menu you are talking about in the video. You warn about it being necessary all the time, yet do not state clearly if this bearing kit contains it or not. Please indicate this CLEARLY for everyone to see, it is really confusing. Apart from that (assuming the kit DOES NOT include the rear, which I seem to deduct from one of the answers for previous questions), why make a bearing kit without the most important and needed bearing? Does ANY kit you sell include this 2010 rear gear pinion bearing (maybe those big kits with bottles for 279$ or any other kits by Ford?) or the only way is to buy the bearing separately?

    • We do apologize that the listing is not clear enough. The Motive Rear End Installation and Bearing Kit does not include the Rear Gear Pinion Bearing for 2010-2014 Mustangs. The bearing is not included in the kit because the kit is designed for 1986-2014 Mustangs, and it is not necessary for the majority of the years this kit works on. It is included in the Gear Combo Kits for the 2010-2014 GT and 2011-2014 V6 Mustangs found here: https://www.americanmuscle.com/2010-mustang-gears.html#shop-by7

    Helpful (5)

    What type of bearing come in this kit? Koyo or Timken?

    • This Motive Rear End Installation and Bearing Kit - 8.8 in. (86-14 V8; 11-14 V6) kit is going to have Timken pinion bearings and Koyo carriers.

    Helpful (3)

    Will this correct speedo for a rear gear change

    • Yes this Bama tuner would be able to calibrate your vehicle for the gear change that you made to it.

    Helpful (2)

    can the Bama SF4/X4 be used to turn off theft system I have a 2003 mustang GT, I've had several occasions when car would not start due to theft system. I would like to bypass/turn off the theft system

    • We can disable this system within a custom tune upon your request.

    Helpful (2)

    Will this work after a engine swap? I own a 2000 Mustang GT 5 speed and was considering purchasing this tuner to wake it up some more. I am in the process of putting a new 4.6 SOHC motor in the car. If I buy this tuner and use it with the 4.6 already in the car will it work when I put the new engine in? The engine is just a rebuilt version of what's already in there.

    • The tuner would still work fine, there shouldn't be any issues with the tune working with a direct engine repalcement.

    Helpful (2) Show 2 more answers
    Post Your Question
    10 More Questions
    Whats the difference? What is the difference between this kit and the kit for 35 dollars? 3 answers
    I plan on adding the 2012 Boss 302 Torsen differential to my 2011 Mustang GT. Is this the proper kit I will need to freshen up rear end when I have the Torsen installed? The stock rear end has about 41k on it and 3.73 gears. And will the kit's cover plate seal work with the aluminum differential cover plate? 1 answer
    I have a bolt on 99 GT ( intake, intake plenum, intake manifold, pulleys, offroad H, 4.10 gears ) would this be able to extract more whp then my current old revision predator u7146 with canned tunes? 1 answer
    Will Bama be able to tune for an Eaton TVS 1900 Supercharger on my 2002 Mustang GT? 1 answer
    Do you know if these kits will fit a 99 f150 4x4 with an 8.8 rear gear? 1 answer
    I am replacing the entire axle housing on my 14' GT. It appears this kit has everything I need for the housing swap. The original housing has damage. I need to confirm if this kit does actually have all the parts needed for the swap. (Besides gear oil) Thank you I already purchased new axles from you guys. 1 answer
    Can i data log AFR and Boost on my X4? 1 answer
    I have a custom exhaust intake and im going to put a smaller pulley on the blower will this device put a custom tune in the car for all that ? 1 answer
    I bought the car tuned already, if I change any of the aftermarket Bolt-ons would it throw the tune off ? 1 answer
    Can this tuner calibrate a 19lb Injector maf sensor to match 24lb injector? 2004 gt with 1997 cobra engine 1 answer

    People Who Bought This Item Also Bought

    Customer Reviews (100+) Write a Review

    Overall Rating 4.8

    out of 5 stars

    Installation Time:Weekend

    Installation Cost:$250-$500

    • Performance Gain 4.622244 4.6
    • Fit 4.897436 4.9
    • Seat Of Your Pants Feel 4.332103 4.3
    • Ease Of Use 4.746324 4.7
    • Bang For Your Buck 4.398524 4.4
    • Preferred Tune: Performance



    • 5/5

      January 14, 2019

      Review from Motive Rear End Installation and Bearing Kit - 8.8 in. (11-14 V6; 86-14 V8, Excluding 13-14 GT500)

      Great kit, has it all!

      This kit is eveything you need to install your gear and pinion. Bought it with the royal purple gear oil, 3.73 gears, and the ford friction modifier because their complete kit was out of stock. Great buy, great deal, great product.

      AdrianT

      Year: 1999 Submodel: GT

      Helpful (0)

    • 5/5

      January 11, 2019

      Review from Ford Performance Ring Gear and Pinion Kit - 3.73 Gears (11-14 V6; 86-14 V8, Excluding 13-14 GT500)

      Quality parts, great for a DD

      I was getting my axle and pinion bearings replaced, so I decided to switch to a 3.73 from my 3.55 while that was being done. Its not a massive difference from a 3.55, but does provide just a little bit more grunt.

      Hs

      Year: 2006 Submodel: GT

      Helpful (1)

    • 5/5

      January 09, 2019

      Review from Bama X4/SF4 Power Flash Tuner w/ 2 Custom Tunes (99-04 GT, Bullitt)

      Amazing

      An absolute must for anyone looking to gain instant horsepower. I followed the tune installation instructions exactly as described, did not have any issues at all. This tuner does exactly what it claims to do, and more. I am absolutely thrilled with the results.

      JamieE

      Year: 2003 Submodel: GT

      Helpful (1)

    • 5/5

      December 27, 2018

      Review from Bama X4/SF4 Power Flash Tuner w/ 2 Custom Tunes (99-04 GT, Bullitt)

      REV X4/SF4 TUNNER

      I PURCHASED THIS A COUPLE MONTHS AGO. THIS UNIT IS EASY TO USE WITH GREAT RESULTS. THE TECHS ON THE PHONE WERE HELPFUL AT SETTING UP MY CUSTOM TUNE. AND BOY WHAT A DIFFERNCE IT MADE. REALLY WOKE UP MY BOLT ON BUILD 4.6 GT. FILLS LIKE A DIFFERNT CAR.

      JoeK

      Year: 2001 Submodel: GT

      Helpful (1)

    • 5/5

      December 26, 2018

      Review from Motive Rear End Installation and Bearing Kit - 8.8 in. (11-14 V6; 86-14 V8, Excluding 13-14 GT500)

      This is your best option to do a rear end rebuild

      Great purchase, i had to do gears on my 99 GT and this kit was the best option.

      RodrigoF

      Year: 1999 Submodel: GT

      Helpful (1)

    • 5/5

      December 25, 2018

      Review from Bama X4/SF4 Power Flash Tuner w/ 2 Custom Tunes (99-04 GT, Bullitt)

      Easy to update and install

      Requested two tunes and received it in a day.. download the tunes in computer and loaded it on the tuner very easy. First time downloading the tunes and I had to update the device for the drivers. After that is was easy and just follow the direction. I will request more tunes after I purchase more mods for the 99 Mustang GT. Thank you AM!

      ReubenCabrera

      Year: 1999 Submodel: GT

      Helpful (2)

    • 5/5

      December 17, 2018

      Review from Motive Rear End Installation and Bearing Kit - 8.8 in. (11-14 V6; 86-14 V8, Excluding 13-14 GT500)

      A must cop!!!

      If youre upgrading your rear end, this will be beneficial. Comes with everything you need.

      MikeJ123

      Year: 2010 Submodel: GT

      Helpful (1)

    • 5/5

      December 15, 2018

      Review from Motive Rear End Installation and Bearing Kit - 8.8 in. (11-14 V6; 86-14 V8, Excluding 13-14 GT500)

      Awesome product for the price

      Definitely recommend this its high quality for the price your paying. No complaints what so ever.

      JeffreyZ

      Year: 2013 Submodel: V6

      Helpful (1)

    • 5/5

      December 15, 2018

      Review from Ford Performance Ring Gear and Pinion Kit - 3.73 Gears (11-14 V6; 86-14 V8, Excluding 13-14 GT500)

      WOO-HOO!

      I'm very pleased with the change in acceleration compared to the stock 3.31's. I hate myself for not doing this change years ago. Can't wait to get back to Sebring to try these out. The 1st gear set was mis-matched and couldn't get a good pattern, but AM shipped new ones after my mechanic called.

      rickydog

      Year: 2010 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Shop Install

      December 12, 2018

      Review from Ford Performance Ring Gear and Pinion Kit - 3.73 Gears (11-14 V6; 86-14 V8, Excluding 13-14 GT500)

      great gear kit

      great gear kit for money and fast shipping a m has great deals

      NickT

      Year: 2000 Submodel: GT

      Helpful (1)

    • 5/5

      December 10, 2018

      Review from Bama X4/SF4 Power Flash Tuner w/ 2 Custom Tunes (99-04 GT, Bullitt)

      Sick wicked power!!!!!!!

      If you have 2000 to 2004 mustang Gt you have to get the tune to wake up your beast!!!!

      RobertB

      Year: 2000 Submodel: GT

      Helpful (1)

    • 2/5

      December 10, 2018

      Review from Bama X4/SF4 Power Flash Tuner w/ 2 Custom Tunes (99-04 GT, Bullitt)

      not worth it

      if you want speed you have to spend the money and get an actual dyno tune

      EfrainC

      Year: 2015 Submodel: GT

      Helpful (1)

    • 5/5

      December 04, 2018

      Review from Bama X4/SF4 Power Flash Tuner w/ 2 Custom Tunes (99-04 GT, Bullitt)

      Good gains

      I bought the Rev-X tuner and it didn’t work so I advise you to stay away from that device and go with the SCT x4. I called American Muscle and they replaced my Rev-X tuner with the x4 and I’m pleased with it. Really good gains, paired with 4.10s in my automatic GT. It corrected my speedometer, and cleared my check engine light. Shifts are really firm and crisp. I’m running the 93 tune and love it. My car used to chirp 2nd gear now it spins going into 2nd.

      RobertO

      Year: 2000 Submodel: GT

      Helpful (2)

    • 4/5

      December 03, 2018

      Review from Bama X4/SF4 Power Flash Tuner w/ 2 Custom Tunes (99-04 GT, Bullitt)

      Works fine

      The process is pretty simple just email them your upgrades they loaded the tune and mail the tuner. If you are putting in injectors make sure you get the one bama can/will tune for as if not you wasted your money some where.

      ChrisN

      Year: 2003 Submodel: GT

      Helpful (1)

    • 5/5

      November 22, 2018

      Review from Bama X4/SF4 Power Flash Tuner w/ 2 Custom Tunes (99-04 GT, Bullitt)

      Makes a big difference

      Bought this as a present for my brother, he only has a 2 valve but it helped a lot with power

      Josh

      Year: 2004 Submodel: GT

      Helpful (3)

    • 5/5

      November 18, 2018

      Review from Bama X4/SF4 Power Flash Tuner w/ 2 Custom Tunes (99-04 GT, Bullitt)

      It’s a great tuner!

      It’s very simple to use and it definitely gets the job done you can feel the difference with the tunes

      AnthonyD

      Year: 2004 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Full Day

      November 18, 2018

      Review from Ford Performance Ring Gear and Pinion Kit - 3.73 Gears (11-14 V6; 86-14 V8, Excluding 13-14 GT500)

      Great gears

      Much better over the factory 3.31s! I daily drive my car and the 3.73s are perfect, more go when you stand in it and still decent fuel mileage. At 80mph in 5th gear I run about 2400rpms

      WilliamA

      Year: 2008 Submodel: GT

      Helpful (2)

    • 5/5

      November 12, 2018

      Review from Motive Rear End Installation and Bearing Kit - 8.8 in. (11-14 V6; 86-14 V8, Excluding 13-14 GT500)

      Great mod!

      I was planning on upgrading my 3.15 gears to 3.73 after winter in the summer. However, my car had other plans. I developed some whining and issues with the rear. Instead of fixing the issue which would have been way cheaper. I decided since I am going to open it up I might as well upgrade. I have a few things to mentions if you are doing it yourself. This job is indeed a very messy job and requires a lot of work. We had done it on jacks, but I recommend finding a shop that can do it for a fair price. It is truly not worth doing it yourself. Also, you will need many specialty tools. Many of which you have to rent and some I had to purchase. Even with the right tools, there is still a lot you have to improvise yourself. Another mention is that you will need to buy a third bottle since you need to lube up the bearings as well as fill up the differential. When it comes to performance the car pulls very hard specifically if you have a tune on the car. I was quite surprised how the car had improved. I would recommend this mod hands down, but you really have to decide if you want to install it yourself.

      LukaszF

      Year: 2013 Submodel: GT

      Helpful (4)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $250-$500

      November 09, 2018

      Review from Ford Performance Ring Gear and Pinion Kit - 3.73 Gears (11-14 V6; 86-14 V8, Excluding 13-14 GT500)

      Woke the car up!

      Aside from the Procharger this rear gear change has really woken up the car. I have to learn the shift timing now that it launches much quicker.

      JJ

      Year: 2014 Submodel: V6

      Helpful (3)

    • 4/5

      Installation Time: Full Day

      November 09, 2018

      Review from Ford Performance Ring Gear and Pinion Kit - 3.73 Gears (11-14 V6; 86-14 V8, Excluding 13-14 GT500)

      04 mustang gt 5 spd

      Liked them a lot brought my car alive better gas mileage than 4.10 gear but not as quick but overall love them

      MstthewJ

      Year: 2004 Submodel: GT

      Helpful (3)

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