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Ford Performance 3.55 Gears and Install Kit (86-09 V8 Mustang)

Item 100575
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      Video Review & Installation

      If you're looking for a little bit more acceleration and performance off the line but without compromising your fuel economy, a set of 3.55s from Ford Performance might just be the solution. Now, this kit will fit the 8.8 solid rear axle in your Mustang and will not only include the brand new ring and pinion as you can see but also everything you need to get them set up and in place. Your price point for this kit will land you right in the mid $200 price range and the install, listen, it's not gonna be for everyone out there, it will require some specialty tools so therefore we're gonna knock this one up to a three out of three wrenches on the difficulty meter with a little bit more detail to come later in the video. So it's no big secret that factory gear ratios on most of these earlier cars, including the fox body, the SN95 but even some of the early S197s weren't exactly ideal for scorching off the line acceleration, in fact, it was quite the opposite. Now most of these earlier cars came with a 2.73, a 3.08 gear or in some cases a 3.27. But that was pretty much it until the S197 ushered in an optional 3.55. But with all that said a lot of guys might not want to make a massive jump to a 4.10 or higher gear ratio maybe for fuel economy reasons or maybe they just don't see the need for it with their particular application and therefore would like to compromise with a middle of the road gear ratio, and in that case I think the 3.55 is a perfect option. And on top of that power adder cars out there might want something to get the car moving a little bit more but don't wanna go with a numerically higher gear ratio as you want the car to stay in boost a little bit longer and not be shifting consistently. So there are many reasons why a gear change is important in your use, and your application is no doubt the biggie. As far as the physical gears and construction is concerned here with this kit, well, nothing but the best from Ford Performance as you might expect, including the strong forge construction, the CNC cut, along with the [inaudible 00:02:05] teeth and then finally the black oxide coating. Everything has been made here in the USA and Ford Performance claims they're gonna be the quietest gears available on the market for your 8.8 rear. Now that last claim in regards to noise should be taken with a grain of salt because a lot of times with a gear install any noise you might receive in the rear end might not always be coming from the gears themselves but rather the installation or the setup which does lead us to the next part of this product and that is the installation kit. Now this is also from Ford Performance and does include everything you need to get that brand new ring and pinion set up in your 8.8, including brand new bearings, new seals, new shims, crushed leaves, pinion nut, some gear marking compound and brush to check your pattern and depth of course, brand new diff cover gasket and even two quarts of the 75 90 gear oil in addition to the required four ounces or 3.8 ounces of your friction modifier. So to put it shortly here guys, a very complete kit and one that will be very beneficial to either you or your mechanic when it comes time to get everything installed. Speaking of the installation, listen guys, gear installs are a bit of an art form and do involve a decent amount of work including some use of some specialty tools. So because of this, we're gonna knock this one up to a three out of three wrenches on the difficulty meter here and maybe a day to a half a day in the garage depending on your expertise and how fast you like to work. Now if you've never done something like this before and you're a little apprehensive to tackle this installation you might wanna shop around to some of your local shops and see what they'll quote you for the install. My guess is it's gonna be somewhere in the ballpark of 500 bucks, give or take. On the other hand, if you've done a few gears installs in your day and this is just another day in the garage for you, you already know what to expect and you're definitely going to save yourself some money on some labor. Another thing to keep in mind here with a gear swap like this is that depending on how drastic you go, your speedometer will more than likely be off considerably and at that point, you should correct it. Now '79 to '98 V8 owners out there can simply swap out that speedo gear and that will be the easiest and most cost-effective way to do this. '99 and newer owners, on the other hand, you can either go about changing this through a handheld tuner or a custom calibration, or you can even grab the Ford Performance speedo recalibration device or box here on the site which is gonna run you about a couple hundred bucks. But wrapping this one up guys, if you're suffering from an extremely tall gear in your V8 powered Mustang and wanna fix that without going crazy, a set of 3.55s from Ford Performance would be a great compromise and you could grab your set right here at

      Product Information

      Features, Description, Reviews, Q&A, Specs & Installation

      Features & Specs

      • Money Saving Combo Kit
      • Ford Racing 3.55 Gears - 8.8"
      • Motive 8.8" Rear End Installation and Bearing Kit
      • (1) Bottle of Ford Racing Friction Modifier
      • (2) Quarts of Royal Purple Max Gear 75w90 Gear Oil
      • Fits 1986-2009 V8 with 8.8" Solid Rear Axle


      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, 1 bottle of Friction Modifier, 2 bottles of 75w90 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 Speedometer Gear, 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 3.55 Rear Gear and Installation Kit is designed for use with 8.8in solid rear axle equipped Mustangs, including the 1986-2009 GT, Bullitt, Mach 1, Shelby GT500 and 1994-1998 SVT Cobra. It will not fit the 1999-2004 IRS equipped Cobra Mustangs.

      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.



      Ford Performance 100575

      CA Residents: WARNING: Cancer and Reproductive Harm -

      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) Ring gear
      • (1) Pinion gear
      • (1) 3.8 fluid oz bottle of Friction Modifier
      • (2) one quart bottle of Royal Purple Max Gear 75w90 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

      Customer Reviews (69)

        Questions & Answers

        10 More Questions

        Will It Fit My Mustang

        • Bullitt - 01, 08, 09
        • Cobra - 93, 94, 95, 96, 97, 98
        • Cobra R - 93, 95
        • GT - 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 00, 01, 02, 03, 04, 05, 06, 07, 08, 09
        • GT500 - 07, 08, 09
        • LX - 87, 88, 89, 90, 91, 92, 93
        • Mach 1 - 03, 04
        • Other - 86

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