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Maximum Motorsports IRS Differential Bushings - Aluminum (99-04 Cobra)

Market Price $287.44 You Save 13% ($37.49)
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  • Item 384304

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    Features & Details

    • Differential Bushings
    • Pinion Angle Adjustable
    • Up to 4.5 Degrees of Adjustment
    • Aluminum Construction
    • Prevent Damage to Differential Housing
    • Minimize Driveline Vibrations
    • Spherical Washers Included
    • Fits 1999-2004 IRS Equipped Cobra Mustangs
    Prevent Differential Damage. Prevent damage to your IRS Rear Differential by replacing your worn stock rubber bushings with a stiffer set of Maximum Motorsports Aluminum Differential Bushings. They allow for proper pinion angle adjustment up to 4.5 degrees to minimize driveline vibrations and will further help to eliminate wheel hop in your Cobra's independent rear.

    Quality Construction. The Maximum Motorsports Aluminum Bushing Kit is designed to prevent the breakage of your rear differential cover that is caused by excessive wheel hop. Wheel hop causes violent movement of the differential, which can cause the differential cover to break at the rear mount. Upgrading to stiffer front and rear aluminum bushings will prevent the violent movement allowed by stock rubber counterparts, ultimately protecting your rear.

    Application. This Maximum Motorsports IRS Aluminum Differential Bushing Kit is designed to fit 1999-2004 IRS equipped Cobra Mustangs.

    Fitment: 1999 2001 2003 2004 Details

    MPN# MMIRSB-40.2

    CA Residents: WARNING: Cancer and Reproductive Harm -

    What's in the Box
    • (1) Rear Differential Mount
    • (4) Spherical Convex Washers
    • (4) Spherical Concave Washers
    • (4) Front Differential Mount Spacers
    • (18) Shim Spacers
    Installation Info
    Tech Specs
    Will it fit my Mustang?

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    Customer Reviews (2) Write a Review

    Overall Rating 5

    out of 5 stars

    Installation Time:Afternoon

    • Handling Improvement 5 5
    • Fit 4.5 4.5
    • Bang For Your Buck 4.5 4.5

    • 5/5

      Installation Time: Less than 1 Hour

      March 05, 2018

      Get this now before you blow your rear end.

      This bushing helps keep the diff/ third member In place without this you’ll get wheel hop on stock bushing and if worn can allow enough flex for your CV axle to snap your carrier cap


      Year: 1999 Submodel: Cobra

      Helpful (6)

    • 5/5

      Installation Time: Weekend

      May 01, 2016

      Hold that IRS in place.

      I acquired my 1st Mustang on 12/29/2014, but had been reading Mustang Mags since 2005. I remember reading about wheel-hop and that the IRS model was famous for it. I quickly discovered what wheel-hop is, how BADLY it effects a hard launch, and how dangerous it can be to the differential. Wheel-hop can crack the Diff cover, causing you to loose all the Diff lubricant without knowing it - that would be a very bad day. The only way to stop the wheel-hop is to come off the gas. That's no fun - the whole idea is to stomp on the gas. With the EXCELLENT step-by-step instructions from Maximum Motor, I dropped my IRS subframe onto a cart that I built to easily move the IRS form under the car. I used one hydraulic jack, 2 jack stands and a wheel chock. The good people at Max Motor will walk you through every step and give you hints for problems you may have. I had the problem of small IRS subframe mounting bolts from the factory on the front of the subframe. Max Motor told me to get the larger 9/16 bolts which American Muscle sells (Item #384321). I added a Diff brace to the nose of the Diff. The brace is standard on 03 and 04 Cobras. Once I got everything back together and broke-in the new 3.90 gear, I tested the assembly. From a dead stop, I hit it hard using the the factory Bridgestone tires. The result: NO WHEEL HOP! It was unbelievable. Since then, I might experience an itsy-bitsy bit of wheel-hop 50 of the time during a hard launch. I think it has a lot to do with how well I take-off. I should add that I replaced the rubber upper and lower control arm bushings with Delrin from Max Motor, too.


      Year: 1999 Submodel: Cobra

      Helpful (6)

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