KellTrac S650 Mustang IRS Bushing Upgrade Kit, Level 2 (KTI-BUK24L2) - 2024–2026 Mustang GT & Dark Horse

The KellTrac Level 2 IRS Bushing Upgrade Kit is the ultimate solution for S650 Mustang owners looking to eliminate factory deflection and unlock consistent, predictable rear suspension performance. Designed to positively locate the IRS subframe, differential, knuckles, and rear lower control arms, this comprehensive kit transforms the rear of your Mustang into a tightly controlled, performance-focused system.

From the factory, rubber bushings throughout the IRS allow excessive movement under load—leading to wheel hop, unstable alignment, inconsistent traction, and premature component wear. KellTrac addresses every major weak point in the S650 IRS by combining their proven Posi-Loc system, spherical lower control arm bearings, monoball toe bushings, upgraded differential bushings, and precision centering sleeves. The result is dramatically improved handling, traction, and driver confidence across street, drag, road course, and autocross use.

Every component is engineered for maximum performance with minimal NVH increase, making this Level 2 kit ideal for enthusiasts who demand serious capability without sacrificing drivability. Whether launching hard at the strip or carving corners under load, this system keeps the rear suspension precisely where it belongs.

Features

KellTrac Posi-Loc System

• CNC-machined lightweight design from 6061-T6 billet aluminum
• Black anodized finish for durability and corrosion resistance
• Precision fitment for maximum subframe control
• Industry-first rear lower design that replaces the factory bushing stop plate
• Zero increase in noise, vibration, or harshness

Rear Lower Control Arm Bearing Kit

• Proven S650-specific spherical bearing design
• Super-strong CNC-machined steel bearing bodies
• Industry-leading durable coating
• 6061-T6 billet aluminum bearing offset spacers
• Proprietary 1-inch spherical bearings
• Precision fitment with minimal NVH increase

Polyurethane Centering Sleeves

• Extremely lightweight, precision-molded design
• Accurately centers the IRS subframe to the chassis
• Zero increase in noise, vibration, or harshness
• Industry-unique polyurethane construction

Monoball Toe Bushing Kit

• OEM-designed, engineered, and manufactured components
• Spherical monoball design for drastically reduced deflection
• Improves toe control and reduces erratic alignment changes
• Significantly outlasts factory rubber bushings
• Zero increase in noise, vibration, or harshness

Differential Bushing Upgrade Kit

• OEM-designed and precision-engineered construction
• Higher-durometer rubber for controlled differential movement
• Proprietary rubber and billet bushing design
• Lowest NVH of any full differential bushing replacement kit
• Reduces driveline shock and component damage
• Lifetime warranty

Benefits

• Reduces wheel hop and improves traction
• Centers and positively locates the IRS subframe
• Improves handling response and overall vehicle feel
• Minimizes unwanted suspension geometry and alignment changes
• Helps prevent premature bushing and driveline component damage
• Can assist in reducing driveline vibrations
• Reduces pinion angle change under heavy wide-open-throttle loads

Fitment

- 2024 Ford Mustang GT
- 2024 Ford Mustang Dark Horse
- 2025 Ford Mustang GT
- 2025 Ford Mustang Dark Horse
- 2026 Ford Mustang GT
- 2026 Ford Mustang Dark Horse

Kelltrac Terms Of Service

Kelly considers his Kelltrac line to be a specialty line for a unique customer base and has his own terms of service in addition to Beefcake Racing's.   You must accept these terms on all Kelltrac orders.   Please read shipping times, cancellation, and returns.  If time is of the essence, we do have other options that can ship right away / quicker.  Just reach out to one of our sales associates at Beefcake Racing.

Cancellations & Returns

KellTrac Innovations does not accept product returns. Once your order ships, you own it and we will not accept it back - NO EXCEPTIONS. We do not accept order cancellations after the product has shipped. If you understand and accept this please check the box and continue checking out. If you do not accept this, please stop and discontinue the order process. Thanks!

Due to the custom nature of our business and product offerings, we charge a 20% order cancellation fee, period, non-negotiable, no matter who you are. Orders can only be cancelled before the product ships. We do not accept order cancellations after the product has shipped. If you understand and accept this please check the box and continue checking out. If you do not accept this, please stop and discontinue the order process. Thanks!

Leadtime

Please be aware that most orders ship within 2-4 weeks. In some (rare) cases, orders can take up to 6-8 weeks to ship. Holidays can severely impact these lead times. *DO NOT CONTACT US ABOUT YOUR ORDER UNLESS IT IS OLDER THAN 20 BUSINESS DAYS!* If you understand and accept this please check the box and continue checking out. If you do not accept this, please stop and discontinue the order process. Thanks!

CA Residents: WARNING: Cancer and Reproductive Harm www.P65Warnings.ca.gov