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New! for Street & Strip Mustangs! Big-bore rear wheel cylinders for 1979-1993 Mustang with 9" drum brakes. Improves braking when running big rear tires and front skinnies, and/or different OEM front brakes.

New! Swapping a Coyote into a Fox Mustang? MM's Hydroboost Conversion Kits allow easy installation of a 1996-2004 Mustang Hydroboost power brake assist unit into a 1979-1993 Mustang.

New! Swapping an IRS into your Fox Mustang? MM makes it easier with a brake line kit made just for this conversion. Bolts-in, with no cutting or flaring of brake lines. Designed to fit standard IRS brake hoses.

New! MM's billet aluminum Pedal Box Spacer for Fox Mustangs. Replace the breakage-prone OEM plastic spacer when converting to manual brakes or Hydroboost.

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We've posted the parts list and link to the video of MM's Mustang in /DRIVE Tuner car Shootout

Extreme-Duty Mustang Rear Lower Control Arms, 1999-2004
Actual product may differ from photo.
  • Extreme-Duty Mustang Rear Lower Control Arms, 1999-2004

click on thumbnail to zoom


  • Item # MMRLCA-31
  • Manufacturer: Maximum Motorsports

Select Option(s):

RLCA option



Maximum Motorsports Extreme -Duty series Rear Lower Control Arms for the 1999-2004 Mustang improve traction and handling by reducing the unwanted deflection allowed by the stock soft rubber bushings and flexible stamped steel control arm. Spherical bearings at both ends of this control arm eliminate the deflection that can cause wheel hop, yet also allow the articulation required for proper handling.

Fits 1999-2004 Mustang with solid rear axle. Includes spring perch and swaybar mount.

Well suited for Mustangs:

  • With up to 1,000 HP
  • That are launched hard from a standing start, meaning a drag race style start from a dead stop, whether on the street or at the strip

Why should I use the Extreme-Duty control arms instead of the Heavy-Duty series?
Mustangs with over 400 rwhp, and even those with less power that are launched hard from a standing start, may overload urethane bushings, leading to premature failure of the bushing. When you hit your Mustang's throttle pedal, all of the forces accelerating your car pass from the rear axle housing through the lower control arms and their bushings; that's what moves your Mustang forward. The harder the car accelerates on launch, the greater the forces on the lower control arm bushings. Higher forces lead to a shorter lifespan of urethane bushings. The oversized spherical bearings used in the MM Extreme-Duty control arms are robust enough for a Mustang with 1,000 HP launching on slicks.

Better by design

  • Stress on the chassis torque-boxes is greatly reduced because the MM design allows proper articulation of the rear suspension.
  • Spherical bearing at each end allows proper suspension articulation, while completely eliminating bushing deflection.
  • Large 2" diameter round steel tube design for highest strength.

Why do I need MM Rear Lower Control Arms?

  • The stock Mustang rear lower control arms are fitted with very large, soft rubber bushings. Those bushings allow the axle to shift fore and aft, causing the toe of the rear tires to change. Toe changes cause instability as the rear of the car steers itself in unpredictable directions. The rubber bushings also allow axle wind-up during acceleration, which in turn causes wheel hop.
  • MM Extreme-Duty Rear Lower Control Arms were designed by our engineering team to completely eliminate fore/aft movement of the axle, while also retaining the suspension's ability to properly articulate. This improves performance with just a small compromise in ride quality.
  • Potential torque-box damage is greatly reduced because the MM design allows the suspension to easily articulate.
  • Manufactured by MM in the USA.


  • Deletion of spring perch and swaybar mount is available by clicking on the option button above.

Related Products

Maximum Motorsports Extreme-Duty Rear Lower Control Arms for 1999-2004 Mustangs


  • Improved traction by eliminating excessive deflection allowed by stock rubber bushings and stamped steel control arm.
  • Greatly reduces occurrence of wheel hop, usually enough to allow removal of quad shocks.
  • Improved handling, stability, and predictability by more precisely controlling movement of the rear axle.
  • Unique design with spherical bearings allows proper suspension articulation.
  • Reduced possibility of torque-box damage because the MM design allows the suspension to articulate properly.
  • Spherical bearings cause only a slight change in NVH, maintaining good street manners.

Maximum Motorsports Extreme-Duty Rear Lower Control Arms for 1999-2004 Mustangs


  • Large spherical bearings at both ends.
  • Strong and stiff 2" diameter round steel tube construction.
  • Spring perch fits stock springs and aftermarket springs with an isolator.
  • Swaybar mount fits stock and aftermarket swaybars.
  • Durable black powder coated finish.
  • Made by MM in the USA. Beware of poor quality copies made overseas.

MMRLCA-31 Extreme-Duty series Rear Lower Control Arms


  • 1999-2004 Mustang with a solid axle

Do NOTfit

  • 1979-1998 Mustang with a solid axle because of the different mounting bolt size used during those earlier model years
  • Fox chassis Fairmont, Zephyr, LTD, and Marquis
  • Fox chassis Thunderbird
  • Fox chassis Lincoln Mark VII

Q: Can I use the MMRLCA-31 in a street or road racing application?
A: Yes. The spherical bearings transmit only a little more noise and vibration than do urethane bushings. Spherical bearings allow all of the articulation needed for proper suspension movement, so there is no binding to hurt handling.

You can read Maximum Motorsports' detailed MMRLCA-31 Rear Lower Control Arm installation instructions before purchase.