Upgrade the rear suspension of select Ski-Doo Backcountry snowmobiles with the FOX Factory Series QS3 Rear Track Shock Kit. Designed for demanding trail and backcountry riding, this refined shock system combines reduced weight, position-sensitive damping, and adjustable compression control for improved ride comfort and bottom-out resistance. The kit features FOX Rifle-Bore shock bodies with internal spiral grooves that redirect oil flow around the main piston in the ride zone, creating a plush initial feel. As the shock approaches the final 30% of travel, the grooves end and force oil through the piston for increased resistance during hard impacts.
The FOX Factory Series model uses a double-digressive aluminum piston, high-pitch spring design, high-volume bearing, optimized reservoir length, and lightweight aluminum and injection-molded polymer mounting hardware. Its QS3 three-position compression adjustment allows quick tuning for changing terrain and riding conditions. The black Type III anodized bodies and orange reservoir caps provide the updated FOX Factory Series appearance, while the fully rebuildable and revalveable construction supports long-term service and suspension customization.
This FOX rear track shock kit is manufacturer part number 853-02-059 and vendor part number 853-02-059. It fits select 2023 and 2024 Ski-Doo Backcountry models, including the 2023 Backcountry 600R E-TEC 146-inch, Backcountry 850 E-TEC 146-inch, and Backcountry Sport 600 EFI, along with 2024 Backcountry X-RS 850 E-TEC, Backcountry X 850 E-TEC, Backcountry Sport 600 EFI, and Backcountry Adrenaline 600R E-TEC configurations listed below. Verify the exact model, track length, and suspension configuration before installation.
Fitment: 2023 Ski-Doo Backcountry 600R E-TEC 146-inch; 2023 Ski-Doo Backcountry 850 E-TEC 146-inch; 2023 Ski-Doo Backcountry Sport 600 EFI; 2024 Ski-Doo Backcountry X-RS 850 E-TEC 146-inch with 1.6-inch track or 154-inch with 2.0-inch track; 2024 Ski-Doo Backcountry X 850 E-TEC 146-inch; 2024 Ski-Doo Backcountry Sport 600 EFI 146-inch with 2.0-inch or 1.6-inch track; 2024 Ski-Doo Backcountry Adrenaline 600R E-TEC 146-inch with 1.6-inch or 2.0-inch track.
Features:
- Brand: FOX
- Model: Factory Series QS3 Rear Track Shock Kit
- Size: Rear track suspension application for select 146-inch and 154-inch Ski-Doo Backcountry models
- Manufacturer Part Number: 853-02-059
- Vendor Part Number: 853-02-059
- Rifle-Bore Bodies: Internal spiral grooves provide position-sensitive damping for a plush ride zone and enhanced bottom-out resistance
- Lightweight Construction: Features a 60% lighter piston and 20% lighter shaft compared with the previous design
- QS3 Adjustment: Three-position compression adjustment enables quick suspension tuning
- Piston Design: Double-digressive aluminum piston supports controlled damping performance
- Mounting Hardware: Aluminum and injection-molded polymer hardware reduces weight
- Serviceability: Fully rebuildable and revalveable for maintenance and custom suspension tuning
- Finish: Black Type III anodized shock bodies with orange reservoir caps
- Fitment: Select 2023 and 2024 Ski-Doo Backcountry snowmobiles
Fitment:
2023 Ski-Doo Backcountry 600R E-TEC 146"
2023 Ski-Doo Backcountry 850 E-TEC 146"
2023 Ski-Doo Backcountry Sport 600 EFI
2023 Ski-Doo Backcountry X 850 E-TEC 146"
2023 Ski-Doo Backcountry X-RS 850 E-TEC 146"/1.6"
2023 Ski-Doo Backcountry X-RS 850 E-TEC 154" 2.0
2024 Ski-Doo Backcountry Adrenaline 600R E-TEC 146"/1.6"
2024 Ski-Doo Backcountry Adrenaline 600R E-TEC 146"/2.0"
2024 Ski-Doo Backcountry Adrenaline 850 E-TEC 146"/1.6"
2024 Ski-Doo Backcountry Adrenaline 850 E-TEC 146"/2.0"
2024 Ski-Doo Backcountry Sport 600 EFI 146"/1.6"
2024 Ski-Doo Backcountry Sport 600 EFI 146"/2.0"
2024 Ski-Doo Backcountry X 850 E-TEC 146"
2024 Ski-Doo Backcountry X-RS 850 E-TEC 146" 2.0
2024 Ski-Doo Backcountry X-RS 850 E-TEC 146"/1.6"
2024 Ski-Doo Backcountry X-RS 850 E-TEC 154" 2.0
2024 Ski-Doo Backcountry X-RS 850 E-TEC 154" 2.5
2025 Ski-Doo Backcountry Adrenaline 600R E-TEC 146"/1.6"
2025 Ski-Doo Backcountry Adrenaline 600R E-TEC 146"/2.0"
2025 Ski-Doo Backcountry Adrenaline 850 E-TEC 146"/1.6"
2025 Ski-Doo Backcountry Adrenaline 850 E-TEC 146"/2.0"
2025 Ski-Doo Backcountry Sport 600 EFI 146"/1.6"
2025 Ski-Doo Backcountry Sport 600 EFI 146"/2.0"
2025 Ski-Doo Backcountry X 850 E-TEC 146"
2025 Ski-Doo Backcountry X-RS 850 E-TEC 146" 2.0
2025 Ski-Doo Backcountry X-RS 850 E-TEC 146"/1.5"
2025 Ski-Doo Backcountry X-RS 850 E-TEC 146"/1.6"
2025 Ski-Doo Backcountry X-RS 850 E-TEC 154" 2.0
2025 Ski-Doo Backcountry X-RS 850 E-TEC 154" 2.5
2026 Ski-Doo Backcountry Adrenaline E-TEC 600R 39in. Ski Stance
2026 Ski-Doo Backcountry Adrenaline E-TEC 600R 43in. Ski Stance
2026 Ski-Doo Backcountry Adrenaline E-TEC 850 39in. Ski Stance
2026 Ski-Doo Backcountry Adrenaline E-TEC 850 43in. Ski Stance
2026 Ski-Doo Backcountry Sport 600 EFI 39in. Ski Stance
2026 Ski-Doo Backcountry Sport 600 EFI 43in. Ski Stance
2026 Ski-Doo Backcountry X 850 E-TEC 146" 39in. Ski Stance
2026 Ski-Doo Backcountry X 850 E-TEC 146" 43in. Ski Stance
2026 Ski-Doo Backcountry X-RS 850 E-TEC 146" 2.0
2026 Ski-Doo Backcountry X-RS 850 E-TEC 146"/1.5"
2026 Ski-Doo Backcountry X-RS 850 E-TEC 154" 2.0
2026 Ski-Doo Backcountry X-RS 850 E-TEC 154" 2.5