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Coil-Over Kit with Springs, fits Bilstein & 1st-Gen Yellow MM Shocks, rear, 1979-2004 Mustang non IRS

Coil-Over Kit with Springs, fits Bilstein & 1st-Gen Yellow MM Shocks, rear, 1979-2004 Mustang non IRS
Actual product may differ from photo.
Other products by Maximum Motorsports

$513.00

  • Part # COP-3

Select Option(s):

Rear Spring Rate Choice
Add second rear lower shock mount?

Description 

MM Rear Coil-over Conversion package with springs fits solid axle-equipped 1979-2004 Mustangs. Does NOT fit IRS shocks.

Fits
  • Bilstein shocks part number series BE5-6418-xx and 24-064187 (requires adding a groove and machining the lower eyelet for a urethane bushing).
  • Bilstein GBE5-6418-xx (MM adds the groove and machines the lower eyelet for a urethane bushing).
  • Yellow 1st-Generation Maximum Motorsports shocks, part number series BE5-6418-xxx and MB-6418-xxx. The diameter of the polished shaft of these shocks is 11mm, and the housing has a machined groove. 1st-Gen Yellow MM shocks were last sold in June 2016.

Aggressive front coil-over spring rates mandate converting your Mustang's rear suspension to a modern coil-over design to achieve the best handling balance. When higher wheel rates are desired, rear coil-overs provide better handling and ride quality than do high-rate stock location springs for your 1979-2004 Mustang.

MM's conversion kit for Fox and SN95 Mustangs allows easy ride height adjustment without changing springs. Our kit:
  • Improves handling and ride quality by swapping the stock-location rear springs for springs located on the shocks.
  • Lets you choose what spring rate is best for how you use your Mustang. A wide variety of spring rates are available.
Required
  • Bilstein shocks must have a groove machined into the shock housing to fit the threaded coil-over sleeve, and the lower eyelet must be machined to accept a urethane bushing. BE5-6418-xx and 24-064187 were not sold with a machined groove. Confirm your shocks have a groove before ordering this MMCO-3. If not contact MM; for $90/pair we will machine the groove in your shocks, remove the lower rubber bushings, and machine the lower eyelet for urethane bushings. Allow 2 weeks turnaround time for this service.
  • Bilstein GBE5-6418 series shocks were modified by MM with a groove.
  • MM shock series BE5-6418-xxx and MB-6418-xxx are easily identifiable; they have a machined groove, and the lower eyelet is suitable for urethane bushings. No further modifications are needed to install this MMCO-3 kit.
  • Best choice! 3rd-Generation MM shocks are coil-over ready, no modifications required, and include many features not available on Bilstein shocks. 3rd-Gen MM shocks use coil-over kit MMCO-22, not MMCO-3.
  • If your Mustang does NOT have an MM Panhard Bar, installing this rear coil-over kit REQUIRES an additional MMSM-2 Lower Shock Mount. Click on the option button above to add a lower shock mount to this order.
  • 2.25" rear coil-over springs.
Notes
  • Does NOT fit IRS shocks.
  • MMCO-3 fits Bilstein shocks and 1st-Generation MM shocks for solid axle-equipped Mustangs. 1st-Gen MM shocks have a yellow housing and are in part number series GBE5-6418-xxx and MB-6418-xxx. The diameter of the polished shaft of these shocks is 11mm.
  • MM no longer stocks grooved Bilstein shocks. A much better choice for rear coil-overs are MM's 3rd-Generation Black shocks.
  • MMCO-3 does NOT fit 2nd-Generation MM shocks (yellow housing); those shocks require the MMCO-20 or MMCO-21 coil-over kit, and are in part number series MMD-RC0xxxx. The diameter of the polished shaft of these shocks is 5/8".
  • MMCO-3 does NOT fit 3rd-Generation MM shocks (black housing); these shocks require the MMCO-22 or MMCO-23 coil-over kit and are in part number series MMD-RC1xxxx. The diameter of the polished shaft of these shocks is 5/8".
  • For help choosing springs, see the MM Guide to Choosing Spring Rates and Dampers.
  • Coil-over conversion is compatible with stock rear control arms.
Still want new grooved Bilstein shocks?
  • Before ordering this COP-3 package, contact MM to arrange for MM to machine a groove in the BE5-6418-H4 (24-064187) shocks, remove the lower rubber bushings, and machine the lower eyelet for urethane bushings. The charge for this service is $90/pair. Allow 2 weeks turnaround time for this service.
Coil-over benefits
  • Ability to choose from a wide range of spring rates, from soft to very stiff.
  • Improves handling (reduces body roll and quickens steering response) without degrading ride quality because the coil-over spring location improves the motion ratio. This allows a much higher wheel rate than is possible with a stock-location spring.
  • Improves ride quality by eliminating a source of friction in the rear suspension, letting the suspension move more freely and thus reducing harshness.
  • Provides easy ride height adjustment.
  • Reduces unsprung weight, which improves handling and ride quality.
  • Allows for easy spring swapping.
  • Ride height can be retained after swapping to springs with a different rate.
  • Allows adjusting corner weights for optimal track performance.
  • Upper shock mounts reduce deflection, improving damper control.

For help choosing springs, see the MM Guide to Choosing Spring Rates and Dampers.

Features
  • Package includes pair of springs.
  • Only fits Maximum Motorsports 1st-Generation (yellow housing) shocks and Bilstein shocks.
  • This is not an ill-fitting universal kit. It is designed to have a snug fit over the shock housing to prevent rattling.
  • Threads are hard-anodized for longevity and easier adjustment of the spring perch.
  • Lower spring perch has Nylon-tipped stainless steel set screws to prevent unwanted rotation.
  • Includes 1 MMSM-2 Lower Shock Mount. If your Mustang does NOT have an MM Panhard Bar, click on the option button above to add a lower shock mount to this order.
Fits
  • Bilstein shocks with a machined groove. Part number series BE5-6418-xx, GBE5-6418, and 24-064187. Requires the lower eyelet be machined to accept a urethane bushing.
  • 1st-Generation MM shocks with flat, darker-yellow housing. The diameter of the polished shaft of these shocks is 11mm, and the housing has a machined groove. Part number series BE5-6418-xxx and MB-4138xxx. 1st-Gen Yellow MM shocks were last sold in June 2016.
Does NOT fit:
  • 2nd-Generation MM shocks with glossy, bright-yellow housing. The diameter of the polished shaft of these shocks is 5/8".
  • 3rd-Generation MM shocks with black housing. The diameter of the polished shaft of these shocks is 5/8".
  • Any shock other than those listed above.

Click here for coil-over FAQs.

We're working on more FAQs for this product. If you have a question, please use our Contact Us page to email your question. We'll answer your question by return email, and also consider it for possible addition to this FAQ section.

MM Rear Coil-Over Conversion Kit Tech

Each MM shock series works with spring rates in a particular range. Choose your springs first, and then the damper valving choice falls into place.

How do I choose which springs to use?
In general, choose springs that provide the handling characteristics and ride quality you want from your Mustang. To determine that:
  • Decide on the performance goal for your Mustang.
  • Consider how you'll use your Mustang most of the time; you want to optimize it for that type of driving.
  • Consider what level of ride quality you want, and then decide what (if any) compromises you'll make to achieve your performance goal.

For help choosing springs, see the MM Guide to Choosing Spring Rates and Dampers.

Which MM dampers go with which springs?
Choose your springs first. That choice dictates the damper series selection.

See the MM Guide to Choosing Spring Rates and Dampers.

You can read Maximum Motorsports' highly detailed MMCO-3 Rear Coil-Over Kit installation instructions before purchase.