Traxxas Springs Rear White Progressive Rate Slash 4X4 TRX6858

Overview

The Traxxas Springs, Rear (White) (Progressive Rate) (2 pcs) TRX6858 are precision-engineered suspension components designed specifically for the Traxxas Slash 4X4 short course truck. These custom-wound progressive-rate springs represent the pinnacle of Traxxas suspension tuning technology, allowing you to fine-tune your RC truck's handling characteristics with exceptional precision. Whether you're competing at the track or bashing off-road, these rear springs give you the adjustability you need to optimise your vehicle's performance across varied terrain and driving conditions.

Progressive-rate springs are a game-changer in the RC hobby, offering a unique advantage that conventional fixed-rate springs cannot match. The progressive design allows for small-bump compliance without compromising the big-hit capability your truck needs when landing jumps or hitting obstacles at speed. This means your suspension will absorb minor ripples and bumps smoothly whilst maintaining the structural support needed for aggressive driving. These white powdercoated springs are not only functionally superior but also maintain a clean, professional appearance that complements any RC short course truck setup.

If you're serious about RC performance—whether you're a seasoned racer looking to dial in your competition truck or an enthusiast who wants to maximise handling on your weekend bashing adventures—these Traxxas springs are an essential tuning tool. The comprehensive range of available rates ensures there's a perfect match for your driving style and terrain preferences.

Key Features

• Progressive-Rate Design — The progressive spring rate allows small-bump compliance without compromising big-hit capability, meaning your suspension responds smoothly to minor impacts whilst maintaining structural rigidity during aggressive landings and high-speed impacts. This dual-nature performance is what sets progressive springs apart from conventional fixed-rate alternatives and why they're favoured by serious RC competitors.
• Custom-Wound for Slash 4X4 — These springs are specifically engineered and custom-wound exclusively for the Traxxas Slash VXL 1/10 4x4 RTR short course truck, ensuring perfect fitment and optimal suspension geometry. This precision engineering means you're getting springs that work in perfect harmony with your vehicle's suspension geometry and design philosophy.
• Colour-Coded Identification — Each spring rate is colour-coded with a white powdercoat finish, making it incredibly easy to identify which rate you're running at a glance. The colour-coding system includes orange (20% softer than stock), green (10% softer), blue (20% stiffer), and pink (10% stiffer) markings, so you can quickly recognise your setup without checking documentation.
• Durable Powdercoated Finish — The white powdercoat finish provides protection against corrosion and wear whilst maintaining an attractive appearance. This finish ensures your springs will last through countless hours of use whilst retaining their vibrant appearance, whether you're running them on a muddy off-road course or a dusty bashing track.
• Sold in Pairs — You receive two springs per package, the correct quantity for rear suspension tuning on your Slash 4X4. Having matched pairs ensures consistent suspension performance across both rear corners of your truck, which is critical for predictable handling and balanced weight distribution.
• Suspension Tuning Precision — These springs are part of Traxxas's comprehensive suspension tuning philosophy, allowing you to adjust your vehicle's ride height, spring preload, and overall suspension stiffness. Understanding how spring rate affects handling is fundamental to getting the most performance from your RC truck, and these springs give you the tools to experiment and optimise.

Technical Performance

In the world of RC suspension tuning, spring rate is one of the most critical variables you can adjust. Spring rate is measured by the amount of force required to compress a spring by one inch—a higher rate number means a stiffer spring that requires more force to compress, whilst a lower rate number indicates a softer spring that compresses more easily. The Traxxas Springs feature a progressive-rate design, which means the spring's stiffness increases as compression increases. This engineering breakthrough allows the suspension to feel compliant over small bumps whilst maintaining support during large impacts and high-speed driving. The progression in spring rate means you get the best of both worlds: a smooth ride quality that maintains traction over rough terrain, and the structural support needed for aggressive driving and landing big jumps. These rear springs are engineered from high-quality materials to withstand the rigours of RC competition and recreational use. The white powdercoat finish protects the steel spring material from corrosion and extends service life, even when used in wet or muddy conditions. When properly matched with appropriate damping (achieved through shock absorber tuning), these springs will support your Slash 4X4 without being too stiff, which would result in a bumpy ride and reduced traction, nor too soft, which would cause excessive chassis roll and bottoming-out. The factory-optimised settings provide an excellent baseline, but the availability of multiple rates (+/- 10% and +/- 20%) allows you to experiment and find the perfect setup for your specific driving style and terrain.

What's in the Box

• Traxxas Springs, Rear (White) (Progressive Rate) x2

Frequently Asked Questions

• What is a progressive-rate spring and why would I want one for my RC short course truck? — A progressive-rate spring has a stiffness that increases as the spring compresses. This means it feels softer over small bumps and ruts, allowing your suspension to absorb minor impacts smoothly, but becomes progressively stiffer as you compress it further, maintaining support during large impacts and jump landings. This design philosophy gives you superior performance across varied terrain without the compromise of choosing between a soft spring (which wallows in corners) or a stiff spring (which harshens the ride over bumps). Progressive springs are particularly valuable for Slash 4X4 owners who want versatile performance whether they're racing at the track or bashing in the backyard.
• How do I know which spring rate I need for my Slash 4X4? — Traxxas provides four progressive-rate options: orange (20% softer than stock), green (10% softer than stock), blue (20% stiffer than stock), and pink (10% stiffer than stock). The factory-installed springs represent an optimised baseline tuned for versatile performance across most terrain types. If your truck feels too stiff and bouncy over small bumps, you might want to try softer springs (orange or green). Conversely, if you experience excessive chassis roll in corners or the suspension bottoms out easily, stiffer springs (blue or pink) would help. The best approach is to start with the factory settings and adjust from there based on your observations during testing.
• Will these springs fit my Traxxas Slash 4X4? — Yes, these springs are custom-wound specifically for the Traxxas Slash VXL 1/10 4x4 RTR short course truck, so fitment is guaranteed. They are designed to work with your truck's existing shock absorbers and suspension geometry. The part number TRX6858 is the correct specification for rear suspension on all Slash 4X4 variants available in the UK market, including the blue, green, orange, and red colour options.
• Do I need to adjust anything else when I change my spring rate? — When you change spring rate, you may need to adjust your shock damping to match. Spring rate and damping go hand in hand; if you've adjusted your springs significantly, the existing damping might need retuning to work optimally. Additionally, changing spring rate might require small adjustments to ride height to maintain your preferred suspension geometry. The Traxxas Suspension Tuning Guide recommends that if you feel the need for a bigger change than one step in spring rate, you should also consider adjusting shock damper settings to maintain the balance between spring rate and damping force.
• What's the difference between these progressive springs and standard fixed-rate springs? — Fixed-rate springs have a constant stiffness throughout their compression range—they compress at the same rate whether you're hitting a small bump or landing a big jump. Progressive-rate springs like these gradually increase in stiffness as they compress, providing initial compliance for small bumps whilst maintaining support under load. This means progressive springs offer superior performance across a wider range of conditions without requiring a compromise between ride quality and structural support. For versatile RC driving, progressive springs generally outperform fixed-rate alternatives.
• How often do these springs need replacement? — Traxxas springs are engineered for durability and long service life. Under normal recreational use, springs rarely wear out or lose their rate characteristics. However, if you notice your truck sitting lower than usual (indicating loss of spring rate), or if a spring becomes bent or damaged in a crash, replacement is necessary. The powdercoat finish protects against corrosion, so these springs can handle wet conditions without concern. Store your springs in a cool, dry location when not in use to maximise longevity.

Why Buy from RC Model Shop?

RC Model Shop is a trusted UK RC retailer and authorised dealer for all the brands we stock, including Traxxas, ARRMA, Losi, FTX, Hobbywing, Spektrum and more. Based in Walsall, we have a physical store where customers are welcome to come in, view products and purchase in store. Whether you are a seasoned competitor, a weekend basher, or just discovering the world of RC for the first time, our team of experienced RC enthusiasts is here to help you find the perfect setup and provide ongoing support. Order the Traxxas Springs, Rear (White) (progressive rate) (2 pcs) TRX6858 today with confidence, knowing you are buying from an authorised retailer with genuine products, expert knowledge and a commitment to customer satisfaction. Shop online or visit us in Walsall — we look forward to helping you get the most out of your RC experience.