Gear Heads · SKU B0CXDTFHR8

Trimmer Gear Head Gearbox Head Replacement

Name: Trimmer Gear Head Gearbox Head Replacement
Brand: YUTACOREX
SKU: B0CXDTFHR8

$37 Amazon rating ★ 4.6

Trimmer Gear Head Gearbox Head Replacement for Stihl FS55,FS56C,FS70,FS56,FS70R Brushcutter Weed Eater Brush Cutter Part No. 4144 640 0100 (Suitable for Trim…

CategoryGear Heads

Part numberB0CXDTFHR8

ConditionNew — aftermarket replacement

What the listing states

Listed as compatible with: Stihl FS55

From our Amazon listing, checked September 25, 2026. Model and part-number matches are the seller's; confirm against the part on your machine.

Compatibility

The seller's listing names these models as compatible. Always confirm the model number stamped on your machine before ordering.

✓Stihl FS55

Not sure which part you need? See our guide: How to measure your bar or How to read the stamp on your guide bar.

Before you buy — how to verify fitment

Measure shaft diameter. Common sizes are 24mm, 25.4mm, and 28mm — check your trimmer manual or measure the drive shaft.
Count the splines. The gear head input must match your shaft spline count (typically 7 or 9).
Check output thread. Verify the thread direction and size for your cutting attachment.
Confirm your trimmer model against the compatibility list above.

Frequently asked questions

How do I know which gear head fits my trimmer?

Match the shaft diameter (typically 24mm, 25.4mm, or 28mm), the number of splines (7 or 9), and the thread direction on the output shaft. Check your trimmer manual for these specs.

Can I replace a gear head myself?

Yes. Remove the old head by loosening the clamp bolt, slide it off the shaft, and slide the new one on. Align the drive shaft splines, tighten the clamp, and check for wobble before running.