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Ford Performance 3.73 Gears and Install Kit (10-14 V8; 11-14 V6)

Market Price $316.99 You Save 12% ($37.00)
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$279.99

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  • Item 100573
  • MPN# 100573

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Ship to: Ashburn - 20149
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    Features, Video & Details

    • Money Saving Combo Kit
    • Ford Racing 3.73 Gears - 8.8"
    • Ford 8.8in Rear Gear Pinion Bearing
    • Motive 8.8" Rear End Installation and Bearing Kit
    • 1 Bottle of Ford Racing Friction Modifier
    • 2 Quarts of Royal Purple Max Gear 75w140 Gear Oil
    • Fits 2005-2014 V8 and 2011-2014 V6 Mustangs with 8.8" Solid Rear Axle

    Review & Installation Video

    Review & Install Video

    Improve ET's and low end torque. Are you looking to get more low end grunt off the line and lower ET's at the same time? Then look no further than installing a set of steeper gears in your Pony. This Ford Racing Ring and Pinion Gears are perfect for street, road, or race use.

    Complete Kit. This Ford Racing Gear and Installation Kit comes complete with all the components needed to swap out your ring and pinion gear. It includes Ring gear, Pinion gear, inner rear gear pinion bearing, 1 bottle of Friction Modifier, 2 bottles of 75w140 Gear Oil, gaskets, seals, shims, bearings and all the required hardware.

    Legendary Ford Racing Quality. When you're adding performance parts to your Pony, you can't go wrong by installing parts from the folks that know it best. Ford Racing's legendary quality ensures years of hassle-free use.

    Recommended Upgrade. Changing the rear axle gear ratio will throw off the calibration of your Mustangs speedometer, but a Ford Racing Speedometer Recalibration Tool or a Bama SF4/X4 Power Flash Tuner is a quick and easy way to fix this issue.

    Application. This Ford Racing 3.73 Rear Gear and Installation Kit is designed for use with 8.8in solid rear axle equipped Mustangs, including the 2005-2014 GT, Bullitt, BOSS, Shelby GT500 and 2011-2014 V6 models.

    Application Note: Does not fit 2013 Boss or 2013-2014 Shelby GT500 Mustangs with axle codes S-215-D and S-219-D.

    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.

    Fitment: 2010 2011 2012 2013 2014 Details

    CA Residents: Warning: California's Proposition 65

    What's in the Box
    • (1) Ring gear
    • (1) Pinion gear
    • (1) Rear Gear Pinion Bearing
    • (1) 3.8 fluid oz bottle of Friction Modifier
    • (2) one quart bottle of Royal Purple Max Gear 75w140 Gear Oil
    • Front & Rear Pinion Bearing
    • Pinion Seal
    • Carrier Bearings
    • Carrier Shims
    • Differential Bearings
    • Crush Sleeve
    • Pinion Nut
    • Cover Gasket
    • Ring Gear Bolts
    • Brush
    • Gear Marking Compound
    • Loctite
    Installation Info
    Will it fit my Mustang?
    • Boss 302 - 12, 13
    • GT - 10, 11, 12, 13, 14
    • GT500 - 10, 11, 12, 13, 14
    • V6 - 11, 12, 13, 14

    Does not fit 2013 Boss or 2013-2014 Shelby GT500 Mustangs with axle codes S-215-D and S-219-D.

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    Questions & Answers (20)

    5 Top Rated Questions

    I am thinking about upgrading to this kit for my 2012 GT. It currently is running on a tune 24/7 because of my boss 302 intake and it is tuned for the stock 3.15 gears. I plan on having this done professionally, I will get a new tune for these 3.73 gears before i take it in. Should i tell the shop not to start the car until i have the new tune for these gears installed?

    • Naw it will be alright your speedo will be off by a few mph's that's all. If you have a manual car I would go 4.10 only if you don't drive it ever day with that 6 gear you almost can't tell. I got that in my car now and let me tell you it's amazing out of the gate......

    Helpful (4)

    "Ford Performance 3.73 Gears and Install Kit (10-14 V8; 11-14 V6)." Hi, i bought these for my 14 v6, still in the box. I'm thinking about purchasing a 17 v6, will this gear kit fit in the 17 v6? Thx

    • This Ford Racing 3.73 Rear Gear and Installation Kit is designed for use with 8.8in solid rear axle models and will not work with the 15+ models due to the independent rear end.

    Helpful (1)

    If I purchase this kit for a 2010 GT, do I still need to purchase the "Rear Gear Pinion Bearing" Item#394003? I remember seeing a video here on AM, and Steph said this would be necessary for the 2010 because the design had changed. Or is there a complete kit for the 2010's specifically?

    • Hello! The Ford Performance 3.73 Gears and Install Kit will have everything necessary for your 2010 GT.

    Helpful (1)

    I can't find a shop in my area that will install this for a reasonable price. If I brought my car to you guys could you install it?

    • Unfortunately we do not currently offer customer installs at this time. I would recommend checking with a Ford dealership as they should be able to do the install without any issues.

    Helpful (0)

    Hi, I have Gt 2011 with stock gears 3.15 my question is wich one is better in drag racing from 0 KM , 40 KM , and 60 KM the 3.55 or 3.73 ? Thanks.

    • The Ford Performance 3.73 Gears and Install Kit will be able to get you off the line much faster than the 3.55 gears will. However, the 3.55 gear ratio will keep pulling at higher speeds than the 3.73s for a longer stretch.

    Helpful (0)
    Post Your Question
    10 More Questions
    Would i Need the whole install kit if i have 73k miles on my car? 1 answer
    Will this kit work for 2010 4.0 v6. 1 answer
    if I were to install these gears would I need to get new axles as well or will stock axles work just as good? 1 answer
    If I install these 3.73s, do I have to change the axles since I'm running on bigger gears? 1 answer
    would these gears fit my stock carrier from my 2014 mustang v6 premium that carried a 2.73? 1 answer
    If I decide to replace the gearing on my own, will I need any specialty tools? And if so, what tools? 1 answer
    Hey for my 2012 mustang this gear setup will high way driving still be fun or will be like my friend with 4.10 gears doing 65 at high rpms And is the extra rebuild kit for traction a must need with this gear kit 1 answer
    Both me and my brother are thinking about upgrading the gears in our cars (mine is a 11 v6 and my brothers is 01 GT) I was wondering what the difference is between your part #s 100573 and 100576 ? 1 answer
    Wondering if this kit will work with a Torsen differential that I plan to install in my 12? 1 answer
    Will these gears slow down my quarter mile time at the track? 1 answer

    People Who Bought This Item Also Bought

    Customer Reviews (82) Write a Review

    Overall Rating 4.7

    out of 5 stars

    Installation Time:Weekend

    Installation Cost:$250-$500

    • Performance Gain 4.831169 4.8
    • Fit 4.727273 4.7



    • 5/5

      Installation Time: Weekend

      November 12, 2018

      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. Unfortunately, when I was purchasing these gears this kit was out of stock. American muscle was only missing the modifier which you don't need since royal purple has it already in it's formula. And they refused to send me the rest of the kit so I had to pay a lot more money to piece it together. 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 (2)

    • 5/5

      August 09, 2018

      A must mod for a V6

      My 2014 is a completely different Mustang after having the 3.73 gears installed and a Bama tune. Super fun to drive now. Thanks American Muscle!

      GeorgeS

      Year: 2014 Submodel: V6

      Helpful (3)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $1000+

      July 29, 2018

      great gears

      Gears went in no problem. Tuned it after I had it installed and made a huge difference

      WilliamC

      Year: 2013 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $250-$500

      July 21, 2018

      Must buy

      Bought gears back in 2016 December had Ford's techs install them if u have a mustang v6 u will love what these 3.73's gears does for your v6 outstanding performance and excelleration from a stand still I highly recommend the 3.73 gears would also recommend getting a tune or calibration tool for speedometer

      battlezack

      Year: 2014 Submodel: V6

      Helpful (2)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $250-$500

      May 12, 2018

      One of the best mods!

      Highly recommend for that edge over others. The response is much quicker. That being said a few tips when getting them installed...1) You are going to need an additional quart of the royal purple oil to fill it correctly 2) do not forget there's a break in period that is recommended. You should drive for about 20-30 minutes then let it cool. And repeat the process several times before opening it up full throttle. 3) The speedometer will be off. Mine was 15mph faster than actual speed and I've seen others including mine become even more inaccurate the faster you go. Over all great product for the price!

      NathanC

      Year: 2014 Submodel: V6

      Helpful (4)

    • 1/5

      Installation Time: Shop Install

      Installation Cost: $500-$1000

      May 10, 2018

      Graet addition

      Really woke up my v-6, the 3.73 gears and with my MPT tune the car pulls hard in every gear. Best addition yet.

      EverettH

      Year: 2012 Submodel: V6

      Helpful (3)

    • 5/5

      Installation Time: Afternoon

      April 27, 2018

      Gears

      Having a skilled background is needed to install, if you have one it’s only a couple hours to install. Performance gains are great for street or strip.

      JeffD

      Year: 2012 Submodel: GT

      Helpful (3)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $250-$500

      April 25, 2018

      373..! V6

      Best bang for your dollar this mod will keep you in your power band make the car alive and highly responsive

      S1972014

      Year: 2014 Submodel: V6

      Helpful (3)

    • 5/5

      Installation Time: Afternoon

      February 14, 2018

      Broke-back Gear...

      Went together like a clock, thanks Kevin for your compassionate and thorough assistance...jhf

      JohnF

      Year: 2012 Submodel: GT

      Helpful (4)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $250-$500

      January 31, 2018

      Oustanding

      Absolutely made a difference on acceleration. Very pleased. Per the reviews, I bought the additional bottle of gear grease. Everything came out perfect. I don't even notice any MPG difference.

      Ryan

      Year: 2014 Submodel: GT

      Helpful (4)

    • 5/5

      Installation Time: Shop Install

      January 22, 2018

      good purchase

      received just what i ordered. customer sevice was very helpful

      AAndrew33

      Year: 2012 Submodel: V6

      Helpful (4)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $500-$1000

      January 11, 2018

      3.73 Ford Performance Gears

      Installed in my 2014 GT/CS Convertible which came with 3.15 gears. Good mileage but sluggish off the line. Had Ford install some Ford Performance 3.73 rear gears. Wow what a difference. It woke my Automatic up. Shifts harder, grabs the road, and mileage suffered only a few mpg's. Love it.

      timber2417

      Year: 2014 Submodel: GT

      Helpful (4)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $250-$500

      January 07, 2018

      Must have MOD...

      My 2011 3.7 with 3:31s seemed lazy, but now with 3:73s it feels like I’m driving a more powerful car because there’s instant throttle response, power and she leaves much faster and throws her rear end out a little. It’s a blast to show off your torque at times. These gears compliment my automatic making smoother transitions between gears with less RPMs, and combined with shorty headers and Flowmasters instantly bring a big smile to my face! These gears will transform your 3.7 into a formidable street contender and you’ll have more fun than a roller coaster.

      DJMustang

      Year: 2011 Submodel: V6

      Helpful (8)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $100-$250

      September 12, 2017

      Great product

      These gears are fantastic! The car pulls way harder and is much quicker off the line. The only downside is whenever I go above 90mph, the car starts to shake. Other than that, great purchase.

      Gilby

      Year: 2014 Submodel: V6

      Helpful (5)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $250-$500

      July 11, 2017

      Totally different car now

      These 3.73 gears change the hole car. The car leaves so much faster and throws the rear end out a little in the 1-2 shift in the auto when accompanied with a Bama race tune. Would 100 recommend this product.

      BM3

      Year: 2014 Submodel: V6

      Helpful (7)

    • 5/5

      June 29, 2017

      Worth the money!

      I've noticed a big difference in acceleration! I have off road x pipe,85mm throttle body, roush intake, res delete and tune and this paired perfectly. Definitely worth the money.

      Chris

      Year: 2013 Submodel: GT

      Helpful (5)

    • 5/5

      Installation Time: Afternoon

      June 21, 2017

      MAKES ALL THE DIFFERENCE!!!

      I threw these in along with a cold air intake and a Bama tuner. The difference is HUGE! This is the way a GT should come from the factory! Makes me smile every time I get on it.

      JoshC

      Year: 2011 Submodel: GT

      Helpful (5)

    • 5/5

      Installation Time: Full Day

      June 13, 2017

      Game changer

      You can definitely feel the improvement to your car! the gears wake up the mustang and really help you get through the gears. MPG will drop by 2-4 especially on the highway with 85 MPH being around 3k RPM in 6th gear. Power is totally worth the MPG drop if that's what you're going for. 250 for the kit and had a Ford tech friend install it for 180, amazing bang for your buck.

      Thomas

      Year: 2014 Submodel: V6

      Helpful (5)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $250-$500

      June 09, 2017

      Best upgrade

      In my opinion 3.73 are the best upgrade for the money , when installed properly these are nice and quiet and rpms didn't go up much at 70

      NikM

      Year: 2013 Submodel: GT

      Helpful (4)

    • 4/5

      Installation Time: Full Day

      June 08, 2017

      3.73 gears

      Well I had these installed Tuesday and picked up the following day. I spent about 600 on the labor. Can't really test these out yet as it's still in the break in period and have to heat cycle the gears. Can't wait to give them a go I've been hearing great things about them. It is a product worth getting.

      JosephA

      Year: 2011 Submodel: V6

      Helpful (4)

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