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

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  • Item 101657

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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.

    Bama Performance

    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?

      Customer Photos

        Questions & Answers (140)

        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)

        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 (4)

        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)

        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 (3)

        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 (3) Show 2 more answers
        Post Your Question
        10 More Questions
        Hello. I need to replace my battery. I was wondering if my tune would erase or what happens if I need to disconnect my battery? 1 answer
        Whats the difference? What is the difference between this kit and the kit for 35 dollars? 3 answers
        Can this product correct the speedometer on a 2000 Mustang GT when it reads high due to running a smaller tire size? 1 answer
        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
        What else do I need to buy with this kit? And does my stick 2014 v6 really need a new 8.8 in bearing or can I use the one already in (if it is already in there)? I’m trying to spend the least amount of money possible right now. 0 answer

          Customer Reviews (100+) Write a Review

          Overall Rating 4.8

          out of 5 stars

          Installation Time:Weekend

          Installation Cost:$250-$500

          • Performance Gain 4.571178 4.6
          • Seat Of Your Pants Feel 4.305263 4.3
          • Ease Of Use 4.731707 4.7
          • Bang For Your Buck 4.370629 4.4
          • Preferred Tune: Performance
          • Fit 4.928571 4.9



          • 5/5

            September 15, 2019

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

            Awesome tuner!

            This tuner is very customizable. You can change injectors size and more right through the options. However, do NOT do like I did and try the demo mode. Took me quite a bit of time and several phone calls to get it fixed.

            mayday65

            Year: 2001 Submodel: GT

            Helpful (0)

          • 5/5

            September 04, 2019

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

            Worked great

            Everything is great so far. The install went smoothly with the shims provided. The only thing I wish had been in the kit would have been an extra oil slinger, so try not to destroy the old one when removing the old pinion seal. Also, put penetrating fluid on your panhard rod bolts like every day for a week before you start this project if you've never had it out before. I had to cut mine out and you don't have a lot of room in there to work a grinder.

            Jeff

            Year: 2005 Submodel: GT

            Helpful (0)

          • 4/5

            September 03, 2019

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

            Great kit for a good price

            Everything needed to do the job is in the kit. Comes packaged separated and neat. Well worth it when installing a new ring and pinion.

            Jackrod

            Year: 2007 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Full Day

            September 02, 2019

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

            Great value!

            Great product! I installed it myself but would highly recommend professional instsll

            JamesW

            Year: 2008 Submodel: GT

            Helpful (0)

          • 5/5

            August 28, 2019

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

            Great product and works good

            Easy and fun to install! I definitely feel like my mustang is back to life

            Matt

            Year: 2000 Submodel: GT

            Helpful (0)

          • 5/5

            August 23, 2019

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

            Worked Great

            Everything you need is here (except a rear pinion bearing which you need to buy separately). I used this Motive Gear kit to install Ford Racing gears with no problem.

            CrazyCooter

            Year: 2014 Submodel: V6

            Helpful (0)

          • 5/5

            August 21, 2019

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

            3.73 GEAR CHANGE

            I ordered the Ford Racing Gear set. it arrived early and I Had a local shop install this. I have only driven about 200 miles but I do notice a difference in acceleration. This plus a custom tune with the BAMA X4 91 Octane performance tune makes my 2007 gt much more fun to drive.

            MIKES2007GT

            Year: 2007 Submodel: GT

            Helpful (0)

          • 4/5

            August 19, 2019

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

            Great tuner

            It's a great tuner noticeable power and shifts way better than stock!! It's easy to use and live data log and live gauges.

            ChrisS

            Year: 2003 Submodel: GT

            Helpful (0)

          • 5/5

            August 18, 2019

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

            Bama x4/sf4

            Love this item. Shipping was on time. Thus is allot better then the super chip I had. Can wait to get to my first custom tune.

            Jman

            Year: 2002 Submodel: GT

            Helpful (0)

          • 5/5

            August 18, 2019

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

            Great Customer Service

            Needed a tuner to turn my PATS off after a auto trans conversion, BAMA did just what I wanted

            JS

            Year: 2002 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Shop Install

            Installation Cost: $500-$1000

            August 11, 2019

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

            3.27 to 3.73

            Very happy with the purchase. Exactly what I ordered and arrived quickly.

            Stangit

            Year: 2003 Submodel: GT

            Helpful (0)

          • 4/5

            July 28, 2019

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

            tuning my 04 sohc 4.6l GT

            I had previously spoken with Justin Bama tune specialist and explained I was having a problem with the tune for my car and he suggested that I try to return to the factory tune and then contact him and we would work on getting my car back on the road. Since then I diagnosed the problem and found a ground plug under the battery box had become semi disconnected and locking the plug together solved the problem, and so now the car is running on the custom tune (93 race ) ,then I fine tune the configuration, and set the nutural idal at 710 and it still idals at 840

            echerzberg

            Year: 2004 Submodel: GT

            Helpful (0)

          • 5/5

            July 17, 2019

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

            Great product

            Great product, make sure to grab the shim kit along with it

            Jgib4

            Year: 1998 Submodel: GT

            Helpful (0)

          • 5/5

            July 15, 2019

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

            Perfect

            Everything you need! Fit great, no issues at all. Would recommend

            ChuckS

            Year: 2001 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Shop Install

            Installation Cost: $500-$1000

            June 30, 2019

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

            FORD PERFORMANCE 3.73

            Satisfied over all had 3.55 stock gears. Went with the 3.73 to help with the cam's

            JasonH

            Year: 2007 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Shop Install

            June 28, 2019

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

            Ring and pinion

            Well the delivery was spot on, had it finally installed, but when the mechanic started to put all back together. Well one hole was not threaded, the ring gear could not be used. Called American Muscle they sent the invoice and gave the number for Ford Performance, they got new ring and pinion set with in 24 hrs. Great customer service from both American Muscle and Ford Performance. Now my 2013 GT/CS has newly rebuilt rear differential and cooks down the Hwy. Only lost 1 day of waiting no big deal. I will still keep on buying parts from American Muscle. Thanks Guys

            Crabber

            Year: 2013 Submodel: GT

            Helpful (2)

          • 1/5

            June 25, 2019

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

            3.73 gears

            Didn’t come with enough shims had to buy more I’ll never shop here again

            RobertGoose

            Year: 1999 Submodel: GT

            Helpful (0)

          • 2/5

            June 21, 2019

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

            Not happy

            I have a near stock 02 gt with a BBK cold air intake and a stright pipe exhaust and applying the 93 octane tune to my car which was in fact running more than 94 octane saw little to no performance gains whatsoever besides horrible horrible I cannot stress enough how horrible the gas mileage was. So I switched it back to the 87 octane street tune even though I was running 92 pump with octane booster. Only improvement I got was better shift timing while driving. Really disappointing

            Larzboss

            Year: 2002 Submodel: GT

            Helpful (1)

          • 5/5

            Installation Time: Afternoon

            June 21, 2019

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

            Awesome acceleration!

            You can't go wrong with ford racing! These gears went in no problem! If you do have the correct tools to set a differential up take it to someone who does. Labor should run about $250.00 These 373 gears and instalation kit is exactly what my 2008 Mustang with a Saleen supercharged called for. I can defiantly fell the difference in acceleration! My 60 ft time has improved along with 1/4 mike times! You won't be disappointed!

            Clint

            Year: 2008 Submodel: GT

            Helpful (1)

          • 5/5

            Installation Time: Afternoon

            June 20, 2019

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

            373 gears

            Installed in an afternoon .nice I went from 331s to 373s

            wildwilly

            Year: 2008 Submodel: GT

            Helpful (0)

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