The Bilstein 5100 is the correct answer for most 4Runner owners who want a meaningful improvement over the OEM shocks without committing to a full suspension overhaul — they fit at stock height or up to 1.5" of lift, they're available for both KDSS and non-KDSS trims, and they last.
**Tools:**
**Parts — choose a tier:**
| Tier | Product | Price | Best for |
|---|---|---|---|
| Budget | Bilstein 5100 set | ~$380 | Stock or mild lift, daily driver |
| Mid | Old Man Emu Nitrocharger Sport | ~$480 | Trail use, loaded overland rigs |
| Premium | Fox 2.0 Performance IFP | ~$699 | Off-road performance, adjustable preload |
| Top | Bilstein 5160 remote reservoir | ~$950 | Repeated high-speed off-road use |
**KDSS note:** The 5th gen 4Runner (2010–2024) Trail, TRD Pro, and some Limited trims come with KDSS (Kinetic Dynamic Suspension System). Shocks for KDSS-equipped vehicles must be specifically valved to work with the system — ordering standard shocks for a KDSS 4Runner causes sway bar binding and over-pressurizes the hydraulic circuit. The Bilstein 5100 has KDSS-specific part numbers. Verify your trim before ordering.
**Front (strut-style front suspension):**
1. Loosen the lug nuts before jacking. Lift the front of the vehicle and place jack stands under the frame rails — not the lower control arm.
2. Remove the front wheel.
3. Disconnect the sway bar end link from the lower strut mount (19mm typically).
4. Unclip the brake line bracket from the strut body.
5. Break loose the two strut-to-knuckle bolts (21mm). These are torque-to-yield bolts on some model years — check a factory service manual if in doubt; replace them if so.
6. Working under the hood, locate the three upper strut mount nuts (usually 14mm) and break them loose before fully removing the lower bolts.
7. Support the lower control arm with the floor jack as you remove the upper mount nuts and the lower strut-to-knuckle bolts. The assembly will drop — control the descent.
8. If swapping shocks only (not the full strut): use a spring compressor to safely compress the front spring, then remove the upper strut nut and separate the shock from the mount hardware. Transfer all mount hardware to the new shock.
9. Reinstall in reverse order. Torque strut-to-knuckle bolts to factory spec (typically 184 ft-lb on 5th gen). Torque upper mount nuts to 30 ft-lb.
**Rear:**
1. Lift and support the rear of the vehicle. Place jack stands under the frame — not the axle.
2. Support the rear suspension (floor jack under the rear differential or axle housing).
3. Remove the lower shock bolt first (usually 17mm), then the upper mount (usually 17mm or 19mm).
4. Note the orientation of the shock — some have a specific mounted angle.
5. Install the new shock, torque lower bolt first (with the suspension at ride height, or close to it), then upper. Factory spec is approximately 72 ft-lb rear lower, 18 ft-lb rear upper on 5th gen.
6. Reinstall rear wheels.
**After both axles:**
Lower the vehicle, bounce to settle. Drive to an alignment shop if you changed ride height — a shock-only swap at the same ride height doesn't require alignment, but confirm visually that nothing has shifted.
For daily-driver 4Runners with mild lift, the Bilstein 5100 at ~$380 for the full set is the correct answer. For built overland rigs running loaded weight over rough terrain regularly, the OME Nitrocharger Sport or Fox 2.0 earn their price premium in damping performance and longevity.
| Part | Vendor | Est. price |
|---|---|---|
| Fox 2.0 Performance Series IFP Shock Set — 4Runner | Fox | ~$699 |
| Old Man Emu Nitrocharger Sport Shock Set — 4Runner | Old Man Emu | ~$480 |
| Bilstein B8 5160 Remote Reservoir Shock Set — 4Runner | Bilstein | ~$950 |
Written and maintained by an AZ wheeler and driveway wrencher. Always cross-reference your factory service manual — modifications affect vehicle safety and warranty. Work at your own risk.