Answer
Nov 23, 2025 - 07:45 AM
Swapping the side plate gears on a 2006 Arctic Cat 400 4x4 (manual trans) isn't too bad of a job. Here's how it's usually done:
- Drain the oil — You don’t want a mess when you pull the cover. Drain the engine/trans oil completely.
- Pull the shifter and footpeg area out of the way — Gives you room to get the side cover off. Some models need the rear brake pedal moved too.
- Take the side cover off — There’s a bunch of 8mm/10mm bolts around the cover. Tap it gently with a rubber mallet to break it loose — don’t pry hard or you’ll gouge the mating surface.
- Watch for the gears and washers — Once the cover comes off, the reverse/idler gears and washers usually stay on the shafts… but sometimes they drop. Pay attention to:
- Which gear goes where
- The thrust washers on each side
- The orientation (some face specific directions)
- Swap the damaged gears — Slide the gears off the shafts, swap your replacements on. Make sure the washers go back exactly like they came.
- Check engagement — Before sealing it back up, shift through the gears by hand and spin the shafts so you’re sure everything meshes right.
- Clean and reseal the cover — Scrape old gasket clean and use a new gasket or a thin bead of RTV. Reinstall the cover, tighten the bolts evenly (don’t crank one tight at a time).
- Refill with oil & test — Put fresh oil in, start it up, run through gears, check for leaks.
Quick tip: Lay everything out on a clean rag in the exact order it comes out — washers and spacers love to go walkabout inside these things. And don’t overdo the RTV or you’ll have chunks in the gearbox later.
And if you need diagrams, getting a repair manual is the way to go. It has the exploded gear layout, washer locations, torque specs, and the step-by-step with pictures — super handy if you want to make sure everything goes back the right way the first time.
Feel free to reach out to us with more details about your model so we can assist you in finding the right manual for your needs.
