Older FOX 36/40 FIT Cartridge: Service Notes and Instructions
Planning to service an older FOX 36/40 FIT cartridge? This guide points you to the archived FOX procedure, “36/40 FIT Cartridge Service”, and explains what to check before starting. It supplements the original instructions; it does not replace them.
What does the procedure cover?
The English-language instructions, bearing a 2008 FOX copyright notice, cover cartridge disassembly, component inspection, reassembly, filling and bleeding. They do not provide a complete step-by-step procedure for replacing every seal in a service kit.
Identify your cartridge before starting
The procedure applies to the older 36/40 FIT cartridge design shown in its illustrations. The name “FIT” alone is not enough to identify a compatible damper. Compare your cartridge with the pictures and construction described in the instructions. Do not assume the specifications apply to later inverted RC2, FIT4 or other damper designs.
Archived service reference photos
These photos illustrate the design and workshop operations shown in the archived procedure. They are reference images, not a standalone service sequence or confirmation of kit compatibility.
Detail at the bladder end.
Removed piston and shaft assembly.
Cartridge assembly using a torque wrench. Refer to the complete instructions for the applicable assembly step and specification.
Image source: FOX, “36/40 FIT Cartridge Service”, © 2008 FOX Factory Inc., via the external archive linked below.
Tools and preparation
You will need a clean workspace, suitable clamping fixtures, the appropriate specialist tools and a torque wrench. Verify the oil specifications and technical requirements for your particular cartridge before starting. Oils supplied with a service kit do not replace this check.
Archived FOX service instructions
Open the complete 36/40 FIT Cartridge Service instructions
This link leads to a third-party archive copy of the FOX document hosted on vitebskbiker.info, not the current FOX website. The instructions are available there as a web page, not a PDF. The reference photos on this page are also loaded from that external archive.
Service kit from Retro Bike Parts
View our FOX 36 cartridge service kit 803-00-149 with RacingBros wiper seals and oils. Before ordering, confirm that the cartridge seals and wipers match your exact fork and damper. Linking to this procedure does not establish compatibility of the kit with every FOX 36 or FOX 40.
Important safety information
Follow the complete original procedure, including all warnings. Incorrect assembly or bleeding can impair damping performance and cause an accident resulting in serious injury. If you are unsure about identification or any part of the work, have the cartridge serviced by a qualified suspension technician.
Need help identifying your service kit? Have the fork's model year and clear photos of the fork and cartridge ready so we can review your enquiry.
Enjoy the ride!
Your Retro Bike Parts team