KellTrac 4/8 Adjustable Lowering Kit w/ Poly-Bearing, STREET STRIP Series (KTI-15F150-48-SS) - 2015-2026 Ford F-150
Improve the stance, handling, and traction of your 2015-2026 Ford F-150 with the KellTrac STREET STRIP Series Adjustable 4/8 Lowering Kit. One of KellTrac's most popular F-150 suspension packages, this is the series that helped establish the company's reputation in the F-150 performance market. Designed for enthusiasts seeking improved performance while maintaining a comfortable ride, this kit combines adjustable front coilovers, triple-adjustable rear Viking shocks, and a rear leaf spring flip kit.
Developed through more than a year of testing, the STREET STRIP Series provides increased front shock travel, adjustable suspension damping, and application-specific shock valving designed for the F-150's leaf spring suspension. Whether used for daily driving, street performance, prepared drag strips, or no-prep racing, this kit offers the adjustability needed to fine-tune ride quality, handling, and traction for different surface conditions.
Adjustable 4/8 Lowering System
The KellTrac STREET STRIP Series is designed to deliver an aggressive 4/8 lowered stance while providing extensive suspension adjustability.
The front ride-height-adjustable coilover system allows drivers to fine-tune the front suspension height to suit their setup. Included coilover conversion mounts feature adjustable shock positioning, providing increased front shock travel compared to other lowering options.
At the rear, the included leaf spring flip kit lowers the truck while retaining its leaf spring suspension configuration. The complete system is designed to improve handling, traction, and overall suspension feel.
Double-Adjustable Front Viking Coilovers
The front suspension features a ride-height-adjustable, double-adjustable coilover system utilizing application-specific Viking shocks and custom Landrum springs.
Adjustable compression and rebound damping allow drivers to fine-tune suspension response for street driving and drag racing conditions.
The included front coilover conversion mounts provide adjustable shock positioning and increased available shock travel, giving the suspension additional flexibility when setting up the truck.
Triple-Adjustable Rear Viking BERSERKER Shocks
A key feature of the STREET STRIP Series is its KellTrac-specific triple-adjustable rear Viking shocks.
These Viking BERSERKER shocks feature specialized valving, stroke, and construction developed for performance with the F-150's leaf spring suspension.
The triple-adjustable design provides additional suspension tuning capability compared to conventional double-adjustable shocks, allowing drivers to optimize rear suspension response for varying traction conditions.
The rear shocks retain the factory mounting locations and include Bilstein high-density foam bumpstops and Monroe shock dust boots as standard equipment.
Spherical Bearing and Polyurethane Mounts
The KellTrac STREET STRIP kit combines high-quality spherical bearing front coilover mounts with high-durometer polyurethane rear shock bushings.
The spherical bearing front mounts provide precise suspension movement for performance-oriented applications, while the rear polyurethane bushings help maintain ride comfort and durability.
This combination provides the responsiveness needed for street and drag strip performance without relying exclusively on rigid bearing mounts throughout the suspension.
Rear Leaf Spring Flip Kit and Driveline Correction
The included rear leaf spring flip kit provides the rear lowering components for the 4/8 suspension configuration.
To address driveline geometry changes associated with lowering the truck, KellTrac includes a rear pinion angle correction kit and a transmission shim kit for use when necessary.
Extremely low-profile rear bumpstops and new rear leaf spring mounting hardware are also included.
Adjustable Front Camber Correction
A front control arm adjustable camber kit is included to assist with alignment following installation.
KellTrac notes that maximum front camber adjustment averages approximately -2.00 degrees. Drivers seeking less negative camber may need adjustable upper control arms or modification of the mounting holes.
Street, Prepared Track, and No-Prep Performance
The STREET STRIP Series was developed and tested specifically for street and drag strip applications.
Its adjustable Viking suspension components allow drivers to fine-tune compression and rebound characteristics to suit changing track conditions, from prepared racing surfaces to no-prep environments.
The combination of custom Landrum springs, increased front suspension travel, and KellTrac-specific Viking BERSERKER rear shock valving is designed to promote traction while improving handling and ride quality.
Kit Includes
- Front ride-height-adjustable, double-adjustable coilover system
- Front coilover conversion mounts with adjustable shock positioning
- Front control arm adjustable camber kit
- Rear stock-location KellTrac triple-adjustable Viking BERSERKER shocks
- Bilstein high-density foam shock bumpstops
- Monroe shock dust boots
- Rear leaf spring flip kit
- Rear pinion angle correction kit
- Transmission shim kit for use when necessary
- Extremely low-profile rear bumpstops
- New rear leaf spring mounting hardware
- Required installation components and hardware
Features
- KellTrac's most popular F-150 suspension kit series
- Designed for 2015-2026 Ford F-150 applications
- STREET STRIP Series adjustable 4/8 lowering kit
- Developed and tested specifically for street and drag strip applications
- More than one year of suspension development and testing
- Developed through innovation involving KellTrac, Viking Performance, and UMI Performance
- Front ride-height-adjustable, double-adjustable Viking coilover system
- Rear triple-adjustable Viking BERSERKER shocks
- KellTrac-specific shock valving, stroke, and design
- Custom Landrum springs specified for the application
- Adjustable compression and rebound damping
- Increased front suspension travel compared to other lowering options
- Adjustable front coilover shock positioning
- Durable spherical bearing front coilover mounts
- High-durometer polyurethane rear shock bushings for ride comfort
- Rear shocks retain factory mounting locations
- Shock valving optimized for leaf spring suspension performance
- Lightweight CNC-machined components
- Designed to improve traction on a variety of racing surfaces
- Adjustability for prepared and no-prep drag racing conditions
- Allows ride quality and suspension performance adjustments
- Designed to improve handling, traction, and suspension feel
- Front adjustable camber correction kit included
- Rear leaf spring flip kit included
- Rear pinion angle correction components included
- Transmission shim kit included for use when necessary
- Bilstein high-density foam shock bumpstops included
- Monroe shock dust boots included
- Extremely low-profile rear bumpstops included
- Precision-fit components designed for consistent performance
- Assembled in-house and ready for installation
- Estimated installation time of 3-5 hours
- All required installation components included
Fitment
- 2015 Ford F-150
- 2016 Ford F-150
- 2017 Ford F-150
- 2018 Ford F-150
- 2019 Ford F-150
- 2020 Ford F-150
- 2021 Ford F-150
- 2022 Ford F-150
- 2023 Ford F-150
- 2024 Ford F-150
- 2025 Ford F-150
- 2026 Ford F-150
Important Fitment and Installation Notes
Towing Restriction: This lowering kit was not designed for towing applications.
Frame Modification: Frame notching may be required in some applications to provide adequate suspension clearance.
Camber Adjustment: Maximum front camber adjustment averages approximately -2.00 degrees. If less negative camber is desired, adjustable upper control arms or slotting the mounting holes may be necessary.
Ride Height: The front coilover system is ride-height adjustable, allowing the suspension to be configured to suit individual lowering goals within its adjustment range.
Intended Use: Designed and tested only for street and drag strip applications, including prepared and no-prep racing surfaces.
Installation: KellTrac estimates a 3-5 hour installation. All required installation components are included. Additional frame modifications or alignment components may be necessary depending on the application.
Vehicle Configuration: Confirm drivetrain, cab configuration, and any application-specific restrictions with KellTrac before ordering, as the supplied fitment information does not specify these details.
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!
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