(approx) 4 Hours
Mechanical expertise or professional installation required.
- Differential Gears - Installation Instructions
Ford Performance 8.8-Inch Rear Axle Bearing and Seal Kit (86-04 V8, Excluding 99-04 Cobra)
Ford Performance Traction-LOK Rebuild Kit with Carbon Discs; 8.8-Inch (11-14 V6; 86-14 V8, Excluding 13-14 GT500)
Ford Performance Traction-LOK Limited Slip Differential with Carbon Discs; 31 Spline 8.8-Inch (11-14 V6; 86-14 V8, Excluding 13-14 GT500)
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 americanmuscle.com.
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Features, Description, Reviews, Q&A, Specs & Installation
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: 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 Details
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November 15, 2019
Awesome works great and easy to install. I had a friend install it on his shop.Helpful (1)
January 17, 2019
Thanks fast shipping items as described thanks !!!!!!!!!!!!!!!!!!!!!!!!Helpful (3)
August 24, 2018
Just what I needed
This was everything that I expected from a Ford Performance product, at a reasonable price. The gear change was a must going from naturally aspirated to supercharged. I previously had 4.10 gears and I'm happy with the outcome of the 3.55 gear selection. It gave me a great balance of power and highway cruising.Helpful (10)
July 31, 2018
nice clean new gears work very well and speeding deliveryHelpful (8)
February 20, 2018
The difference in acceleration is noticed, but you don’t sacrifice highway drivability!Helpful (13)
November 18, 2017
I purchased a high mileage 07 GT that definitely needed the rear ending rebuilt. This kit has all the parts to make it work like it did from the factory.Helpful (11)
October 16, 2017
Great gears for 93 with AOD transmission. Item shipped quickHelpful (10)
October 02, 2017
All quality parts. Installation was simple. Removal of old was a pain... Set-up and alignment with new diff was time consuming but not hard. Installed in a crown vic police and ended up needing a little more oil than the 2qts provided. Overall great kit, would recommend to anyone.Helpful (10)
September 16, 2017
Nice upgrade. Takes off a lot quicker and helps overall acceleration.Helpful (10)
July 24, 2017
It's a great kit!
This is the best deal you'll find on gear kit! The only downside is you only get 2 quarts and it takes more than that. Other than that it's great!!Helpful (13)
If the 8.8 requires 3 quarts of gear oil why are there only 2 quarts included in the "complete" kit?
The fluid capacity of the 8.8 rear for 1986-09 Mustangs is 2qts of gear oil or approximately 3.8 pints.
What other bearings are needed to rebuild my diff that arnt included in this kit
The Ford Performance 3.55 Gears and Install Kit will include front and rear pinion bearings, carrier bearings, differential bearings. In addition to this, axle bearings would be required to completely rebuild your rear end.
Would this be a good gear ratio for a person who uses his car as main mode of transportation?
Yes, 3.55 is a good performance option for a daily driven Mustang.
If I install these in my 95 Mustang Gt. Will I also need to get a Ford Speedo Gear to keep speedo right? I be using these to replace a set of 3.09 stock gears..
When installing the Ford Performance 3.55 Gears and Install Kit you will need to install a speedo gear to correct your speedometer reading. You will require either a 23T speedometer gear paired with your stock 8 tooth drive gear, or a 7 tooth drive gear paired with a 20T speedo gear. We typically recommend against 23t speedo gears, as they have a tendency to wear rapidly.
Have a 2006 GT Automatic is this too high of a gear to install?
This gear ratio would not be too high no! If you drive some back roads and highway this would be a very good ratio to go with.
There is a possibility your GT already has those gears, just as it is possible you are upgrading or downgrading. If you are going up in your gear ratio, your 0-60 will be faster, lowering your overall top speed. If you are going down in ratio, your 0-60 will be slower, raising your overall top speed.
If you have an automatic, you need a tune to adjust your shift points. Otherwise, you're good to go.
Changing your gear ratio is a mechanical change that will not directly effect your performance or gas mileage. However, the higher the ratio, the quicker your 0-60 will be. Typically when one can get from 0-60 faster, they generally do, so "in practice" the 3.73 will hurt your gas mileage more. Again, This is not a direct result, and if you drive exactly the same as you did before this modification, you would notice no differences.
As long as you have the 8.8" Solid Rear Axle, this kit will work.
We would highly recommend torquing down all of the hardware in this Ford Performance 3.55 Gears and Install Kit to factory specifications
Unfortunately the Ford Performance 3.55 Gears and Install Kit will not work with an 03-04 Cobra with IRS. This kit only fits the 93-98 Cobra.However we do sell the gears (Part #50166G94SE) and the install kit (Part #21201) separately for and 03-04 Cobra with IRS. Along with those items you would also need a bottle of Friction Modifier (Part #50377) And 3 quarts of oil (Part #45003) to mimic this kit.
With the Ford Performance 3.55 Gears and Install Kit, you will want to get a tune to reprogram your speedometer in your car.
If your car already has 3.55 gears this will basically be the same kit. There will not be any improvements of this kit over stock.
If you have a manual Mustang, you will need the Ford Speedo Gear - 21 Tooth (83-98 Manual), item # 53682, (http://www.americanmuscle.com/speedo-gear-21tooth-manual.html). If you have an automatic, you will need the Ford Speedo Gear - 21 Tooth (83-98 Automatic), item # 53685, (http://www.americanmuscle.com/speedo-gear-21tooth-auto.html).
You will need a 23T speedo gear. Also, remember to get the correct gear for an automatic or manual. The colors will be different.
(approx) 4 Hours
Mechanical expertise or professional installation required.
What's in the Box