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Riaction Sport Coilovers Lexus GS300 (1998–2005)

Original price $1,000.00 - Original price $1,000.00
Original price $1,000.00
$1,000.00
$1,000.00 - $1,000.00
Current price $1,000.00

Upgrade the suspension on your 1998–2005 Lexus GS300 with the Riaction Sport Coilover Kit. Designed for street-focused enthusiasts looking for a lower ride height, improved handling, and comfortable everyday performance, the Sport Series combines extensive adjustability with durable, fully rebuildable monotube dampers.

This GS300 configuration features 10K front and 8K rear spring rates for a responsive, balanced suspension setup. With 32 levels of damping adjustment and full-length ride height adjustment, the kit gives you the flexibility to fine-tune both suspension response and vehicle stance for daily driving, spirited street use, and performance-oriented builds.

32-Level Damping Adjustment: Fine-tune damper response through 32 settings to suit your driving style, road conditions, and suspension setup.

Full-Length Ride Height Adjustment: Allows you to dial in your preferred ride height while maintaining proper damper operation.

Monotube Damper Design: Provides consistent damping characteristics and efficient heat dissipation during demanding driving.

10K Front / 8K Rear Spring Rates: Chassis-specific spring rates provide responsive handling and increased suspension control while remaining suitable for street use.

52mm Carbon Steel Shock Bodies: Seamless electroplated carbon steel construction provides strength and long-term durability.

44mm High-Flow Aluminum Pistons: CNC-machined 6061 aluminum pistons provide precise and consistent damper operation.

CNC Aluminum Floating Pistons: Lightweight 6061 aluminum construction complements the monotube damper design.

SAE9254 Cold-Wound Springs: High-strength spring construction designed to provide consistent suspension performance.

Low-Gas Pressure Design: Engineered to provide controlled damping while maintaining street-oriented ride characteristics.

Fully Rebuildable: Serviceable damper construction allows the coilovers to be rebuilt to help extend their usable service life.

What's Included

  • (1) Riaction Sport Coilover Kit
  • Front coilover assemblies
  • Rear coilover assemblies
  • 10K front springs
  • 8K rear springs
  • Adjustment hardware where applicable

Vehicle Fitment

  • Lexus GS300 (1998–2005)

Specifications

  • Series: Sport
  • Damper Design: Monotube
  • Damping Adjustment: 32 levels
  • Ride Height Adjustment: Full-length
  • Front Spring Rate: 10K
  • Rear Spring Rate: 8K
  • Shock Body: 52mm seamless electroplated carbon steel
  • McPherson Piston Rod Diameter: 20mm
  • Non-McPherson Piston Rod Diameter: 14mm
  • Main Piston: 44mm high-flow CNC 6061 aluminum
  • Floating Piston: CNC 6061 aluminum
  • Oil Seal: Polyurethane
  • Spring Material: SAE9254 cold-wound steel
  • Valving: Multi-thickness shims
  • Suspension Fluid: 7.5W compounded suspension fluid
  • Damper Construction: Fully rebuildable
  • Warranty: 2-year factory warranty against manufacturing defects

Important Notes

  • Fits Lexus GS300 models from 1998–2005.
  • Factory spring rates for this configuration are 10K front and 8K rear.
  • Features 32 levels of damping adjustment.
  • Professional installation is recommended.
  • A four-wheel alignment is recommended after installation or ride height adjustment.
  • International customers should contact Riaction Performance Shocks regarding international ordering requirements.

Why Choose Riaction Sport Coilovers?

Riaction Sport Coilovers provide GS300 owners with a versatile suspension upgrade focused on street performance, adjustability, and serviceability. The combination of 32-level damping adjustment and full-length ride height adjustment gives you control over both the vehicle's stance and suspension response.

With 10K front and 8K rear spring rates, durable monotube dampers, CNC-machined internal components, and a fully rebuildable design, the Riaction Sport Series is a strong option for GS300 owners looking for sharper handling and an adjustable lowered stance while maintaining street-oriented usability.

About Us

We are passionate Lexus and Toyota enthusiasts dedicated to providing the highest quality aftermarket parts to enhance your ride. Our goal is to help you find the perfect performance upgrade, whether you're building your dream car or just adding that next improvement. We take pride in offering products that we trust for our own vehicles.

Shipping

Shipping times vary based on item availability and specific lead times. You can expect an email with an estimated shipping date within 1-3 days of placing your order. Many in-stock parts ship within 2-5 business days, while certain built-to-order items may take up to 7-10 business days. For back-ordered items, availability may vary, but we will email you with any ETA changes.

Once your items are ready to ship, we will send tracking information via email so you can easily follow your package from our warehouse to your door. Please note, some parts may be shipped separately and could arrive at different times. Shipping costs apply to the lower 48 states, unless stated otherwise, and international orders may be subject to additional customs or duties fees.

What to Expect Upon Delivery

Upon receiving your order, please inspect the items immediately for any damage or missing parts. Verify all items against the packing slip or instructions before starting installation. We cannot be held responsible for costs incurred from delays due to missing items.

If any items are damaged or missing, please get in touch with us within 14 days of receipt so we can assist with a replacement. Claims made after this period will not be honored.

Cancellation Policy

If you need to cancel or modify your order, please contact us as soon as possible. We strive to ship your order quickly, and once processing begins, cancellations may be subject to a restocking fee. Orders canceled within 24 hours of purchase may not incur a fee, but after that time, restocking fees (typically 20%) will apply depending on the items and the stage of fulfillment.

Return Policy

Customer satisfaction is our priority, and we are happy to assist with returns. However, due to the complexity of sourcing and delivering our products, returns are subject to a restocking fee (usually 20%) based on the item and manufacturer.

Before returning any items, please get in touch with us to receive a return authorization. All return requests must be made within 30 days of receiving your merchandise. Once approved, items must be returned within 14 days in their original condition. Improper packaging of returned items may result in customer responsibility for damages.

Customers are responsible for return shipping costs, unless the item is defective or we shipped the wrong item. A trackable shipping method is strongly recommended.

Warranty

We honor all manufacturer warranties and are here to support you in getting the quality products you deserve. However, please note that warranty claims are available to the original purchaser only. In certain situations, manufacturers may handle warranty claims directly, and we are unable to cover costs not specified in the manufacturer's warranty (e.g., shipping, labor). If you have any questions, feel free to reach out to us.

Emissions Notes

All parts and services offered by LunaticsCo are for competition vehicles only. Use on state and federal highways may be a violation of the EPA Clean Air Act. The Clean Air Act can be found at http://www.epa.gov/air/caa/. This document details what are considered violations of the CAA and the corresponding penalties for failure to comply. It should be read in full before purchasing or installing this competition-use-only product. Ensuring that all emissions, noise/sound, and speed/use-related laws are followed is the responsibility of the buyer(s). Installation and use of this product indicate that this disclaimer has been read, acknowledged, and fully understood by both the buyer(s) and installer(s). The buyer(s) assume all associated risks of purchase.

Federal and several state laws prohibit the removal, modification, or rendering inoperative of any part that affects emissions or safety on motor vehicles used on public streets or highways. LunaticsCo assumes no liability for any violations arising out of any federal, state, or provincial emissions or safety requirements on motor vehicles resulting from the customer’s modifications and/or use of LunaticsCo products. It is the responsibility of the customer to determine if their modified vehicle complies with applicable laws.