Suspension school · Brand-Specific Technology

Fox GRIP X, GRIP SL, FIT4 and GRIP

Fox's trail and XC dampers, current and previous generation

In 2024 Fox retired both the FIT4 and the original GRIP damper and rebuilt the entire range for model year 2025 around three new units: GRIP X2 at the top, GRIP X for trail and GRIP SL for cross-country. This article covers the trail and XC dampers from both eras.

GRIP X (2025 Onwards)

GRIP X is the mid-tier trail damper fitted to the 34, 36 and 38, and later the 34 SL and 36 SL. It has three adjusters: high-speed compression, low-speed compression and a single low-speed rebound dial. There is no external high-speed rebound.

The clever part is the HSC dial. It is a long sweep adjuster whose final detent is a firm climbing mode that closes both compression circuits, with a blow-off so a square edge will not spike through the bars. This means a GRIP X fork can effectively be locked out for a road climb, while the more expensive GRIP X2 cannot.

For model year 2027, announced in April 2026, Fox revised GRIP X with a redesigned mid-valve and deleted the firm mode entirely. If your GRIP X has no firm detent at the end of the compression sweep, it is the 2027 version.

GRIP SL (2025 Onwards)

• The XC race damper that replaced FIT4, fitted to the 32 Taper-Cast, 32 Step-Cast and 34 Step-Cast, and later the 34 SL
• Three-position lever (Open, Medium, Firm) plus a low-speed rebound dial
• About 60g lighter than the FIT4 it replaced, using a coil-backed internal floating piston instead of a bladder
• Available with a remote lockout option for race bikes

FIT4 (Up To 2024)

FIT4 was Fox's three-position trail and XC damper for a decade, fitted to Factory and Performance Elite forks. The lever gives Open, Medium and Firm modes. Factory versions add a small dial in the centre of the lever with 22 clicks of low-speed compression fine tuning that works within Open mode.

• Identify it by the three-position lever on the top cap on a model year 2024 or earlier fork
• Centre dial present means Factory, absent means Performance Elite or Performance
• Ride it in Open on anything technical, and treat Medium as a fire-road mode rather than a descending setting

Base GRIP (Up To 2024)

The original GRIP was the workhorse damper on Performance and Rhythm forks: a simple, robust semi-open cartridge that tolerates neglect better than most. Air pressure and volume spacers do most of the tuning work on these forks, and that is fine.

• Rhythm forks: a two-position sweep from open to firm, usable anywhere in between, plus rebound
• Performance forks: a three-position sweep (Open, Medium, Firm) with micro positions between, plus rebound
• Set pressure from Fox's weight table, set rebound so the fork returns quickly without bouncing, and spend your remaining effort on volume spacers

Which Do You Have?

• Sweep lever with no separate HSC dial on a pre-2025 fork: base GRIP
• Three-position lever, pre-2025: FIT4 (centre dial means Factory)
• Three-position lever with GRIP SL lettering, 2025 on: GRIP SL
• Three separate adjusters marked HSC, LSC and rebound, 2025 on: GRIP X