Rebuilding Air Springs in Fox Float DPS Units Step by Step

ByMichail

Start by fully depressurizing your Fox Float DPS shock using a FOX pump-release air until no hissing remains, then remove the black cap to confirm zero pressure. Unthread the air can counterclockwise with a rag through the eyelet, inspect the shaft for damage, and clean it thoroughly. Replace o-rings from the 803-D142 kit, lubricate with Slick Honey, and torque the base nut to 5.7 Nm. Set the IFP depth to 2.15 in (54.61 mm) using tool PN: 803-00-566, prefill with 10–15 cc of FOX 10wt green oil, reinstall the air can, and hand-tighten. Re-pressurize to 250 psi and confirm smooth extension-if the shaft sticks, seek professional service. There’s more to get right for long-term performance and trail reliability.

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Notable Insights

  • Fully depressurize the shock using a FOX pump and confirm no pressure remains before starting.
  • Remove the air can carefully and inspect the air shaft for damage or debris.
  • Replace all air spring O-rings with new ones from the FOX 50-hour service kit.
  • Lubricate O-rings and shaft with Slick Honey to ensure smooth operation and sealing.
  • Reassemble the air can, torque the base nut to 5.7 Nm, and prefill with 10–15 cc of FOX 10wt oil.

Depressurize the Fox Float DPS Shock Fully

Before you even think about cracking open that Fox Float DPS, you’ve got to make certain it’s completely depressurized-safety’s the name of the game here. Always wear safety glasses and protective gloves to prevent injury from sudden pressure release. Use your FOX shock pump to slowly release all air from the main air chamber through the Schrader valve core. Keep bleeding air until no hiss is heard-only then is the shock fully depressurized. Confirm it’s safe by removing the black air cap; if the shock body retracts into the air can, don’t proceed-contact a FOX service center. Never attempt to disassemble the shock unless fully depressurized, as trapped air can launch parts with dangerous force. Depressurize the shock properly, every time, to protect yourself and guarantee smooth maintenance. Safety first, always.

Remove the Air Can and Prepare the Shaft

While the shock’s fully depressurized, you’re good to pull the air can and start prepping the shaft for rebuild-just make certain you’ve already taken off the blue air cap and bled every bit of pressure using your FOX shock pump. Confirm complete depressurization by checking for retraction; if the shock body pulls back into the air can with suction, don’t proceed-contact FOX or an Authorized Service Center. Use a cloth rag threaded through the body eyelet to unthread the air can counterclockwise. Once removed, inspect the air shaft and seal contact surfaces for scratches, dings, or debris. Clean thoroughly with a lint-free cloth rag. Apply a light film of Slick Honey or FOX-approved lubricant to the air shaft and inside the air can. This guarantees smooth retraction and extends seal life. Proper lubrication and inspection are key for reliable performance on long trail sessions.

Rebuild the Air Spring With Fresh O-Rings

Since the air can’s off and the shaft’s prepped, it’s time to refresh the air spring with new o-rings from the FOX 50-hour service kit (803-D142). Start by replacing the air sleeve o-rings, making sure each one is fully seated and untwisted. Apply a thin, even layer of Slick Honey to the o-rings and the air shaft’s seal surfaces-this prevents leaks and cuts friction. Reinstall your chosen negative air spring tokens, keeping them clean and oil-free for accurate tuning. Slide the air can back into place on the Fox Float unit, aligning the eyelet with the air sleeve port. Hand-start the base nut, then torque it to 5.7 Nm (50 in-lb) for a secure seal. Once reassembled, slowly pressurize the main chamber and cycle the stroke 10–20 times past 25% travel to balance the positive and negative chambers and avoid over-pressurization.

Lubricate and Install the IFP to Specified Depth

Grab your FOX IFP depth setting tool (PN: 803-00-566) and start by applying a thin, even film of Slick Honey grease to the inner walls of the shock body-it’ll help the IFP slide in smoothly and prevent o-ring damage during installation. When inserting the IFP, make sure the slot faces upward and the concave side is visible, so it seals properly against the nitrogen chamber. Use the FOX IFP depth setting tool to set the correct IFP depth, like 2.15 in (54.61 mm) for a 190×40 shock. For FLOAT DPS Standard Size units, IFP height ranges from 1.510 in to 2.790 in, with ±0.020 in tolerance. Measure from the rim-the tallest part of the IFP-to guarantee accuracy. Proper IFP installation maintains 500 psi pressure across all models, guaranteeing consistent performance and reliable damping response.

Prefill With FOX 10WT Oil and Reinstall Air Can

After lubricating the IFP and setting it to the correct depth, you’re ready to prefill the shock body with FOX 10wt green oil before reinstalling the air can. Slowly pour the oil down the side of the shock body to reduce aeration and let trapped air escape naturally-this guarantees clean lubrication of the internal components. For most FLOAT DPS models, the recommended oil volume is 10–15 cc of FOX 10wt green oil, but always confirm based on your specific unit. Once prefill is complete, carefully slide the air can back onto the shock body, making sure the threads engage fully and straight to avoid cross-threading. Hand-tighten the air can securely, then align the sticker markings for consistent orientation during future servicing and adjustments. Proper prefill and reassembly support smooth performance and long-term durability.

Test for Proper Extension and Adjust Settings

You’ve got the air can seated and the shock prepped with 10–15 cc of FOX 10wt green oil, so now it’s time to verify everything’s working like it should. To test for proper extension, re-pressurize the shock to 250psi in the positive chamber. If the shock doesn’t extend, suspect internal damage or IFP issues. Never proceed if it’s stuck down-contact FOX or an Authorized Service Center. Make sure the IFP is set to 2.15in (54.61mm), slot up, for proper travel limiter compatibility. After reassembly, add air in 50psi increments, equalizing chambers by compressing the shock 25% of travel 10–20 times per step. Avoid rapid air release to prevent negative chamber over-pressurization, which can cause compression failure. Proper shock extension ensures reliable performance on technical trails, especially when loaded with backpacking gear.

On a final note

You’ve got this. Rebuilt your Fox Float DPS with fresh O-rings, 10wt oil, and proper IFP depth-now it’ll respond faster, extend smoother, and track terrain better. Pair it with a well-tuned fork, dial in your sag (aim for 25–30%), and hit mixed trails confidently. Testers report crisper bump absorption and less stiction over long descents. For backpacking rides, this reliable setup cuts fatigue, so you roll further, faster, with control right where you need it.

Hey there, fellow trail seekers! I’m Michail, the guy behind RideGearLab.com, and I’m just a mountain‑bike enthusiast who loves the smell of fresh pine, the click of a clean drivetrain, and the rush of a well‑planned singletrack adventure. From road rides to off‑road escapades, I’m constantly chasing better gear, sharper technique, and that perfect balance between speed and safety.
My love affair with biking started on a dusty back‑country trail near my hometown, where I rode a battered hardtail with a makeshift frame and a borrowed helmet. I spent weekends mapping routes on paper, tinkering with brakes, and learning how to fuel up with the right carbs before a long climb. Those early rides taught me the basics of trail navigation, bikepacking pack‑outs, and the importance of a solid maintenance routine—lessons I still carry on every ride.
RideGearLab.com is my way of turning those personal experiments into a shared playground. It’s not a textbook; it’s a friendly garage where I post gear reviews, skill drills, route sketches, training tips, nutrition hacks, and safety checklists—all from the perspective of a passionate rider who’s still learning. I want to help you fine‑tune your cadence, pack smarter for a weekend adventure, and keep your bike humming with a little DIY love.
So grab your helmet, check your tire pressure, and join me on the trail. Whether you’re chasing a new summit, planning a bikepacking odyssey, or just looking for a reliable source of riding advice, RideGearLab.com is here to keep the wheels turning and the community rolling. Let’s ride together!

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