P021046670 Trimmer Gear Head Replacement

§ Gear Heads · SKU B0D95QMZRW

P021046670 Trimmer Gear Head Replacement

$36 ★ 4.2

P021046670 Trimmer Gear Head Replacement for Echo SRM-225 SRM-225i SRM-2620 SRM-3020 SRM-225U SRM-266U SRM-280U String Trimmer/Brushcutter Weed Eater Brush C…

CategoryGear Heads
Part numberB0D95QMZRW
ConditionNew — aftermarket replacement

Fitment last verified:

Compare similar parts Check price & availability


Overview

The gear head is the business end of your trimmer, and when it goes bad the whole tool becomes useless. This gear head provides a factory-spec replacement at a fraction of dealer cost. It ships pre-packed with lubricant so you can install and go.

Key specifications

  • Type: aftermarket replacement gear head
  • Pre-greased: yes
  • Material: die-cast aluminum housing with steel gears

Compatibility

Compatible with Echo SRM-225 SRM-225i SRM-2620 SRM-3020 SRM-225U SRM-266U SRM-280U and other trimmers sharing identical drive-shaft geometry. Cross-reference the OEM part number listed in your owner’s manual with the compatibility table to confirm this gear head will work on your machine.

Installation notes

Remove the cutting attachment and unbolt the old gear head from the shaft tube. Inspect the drive shaft splines for damage before installing the new head. Slide the replacement onto the shaft, ensuring the splines engage fully, and secure the clamp bolts. Mount your preferred cutting attachment, start the trimmer at low RPM, and check for unusual vibration or noise.

Common questions

Q: Will this P021046670 gear head fit my Echo SRM-225, or is it only for the later SRM-2620 and SRM-3020 models?

Yes, this gear head is made to fit the Echo models listed here, including SRM-225, SRM-225i, SRM-2620, SRM-3020, SRM-225U, SRM-266U, and SRM-280U. It is used as a replacement for part number P021008182, so the safest check is to match your original gear head or parts diagram to that number before installing.

Q: I have an Echo SRM-266U brushcutter. Does this replacement come as the complete gear head housing, and can I reuse my existing blade or trimmer attachment?

This replacement is for the gear head assembly itself, so in most cases you will transfer over your existing cutting attachment hardware if it is still in good condition. As long as your SRM-266U uses the matching P021008182-style gear head setup, your original blade or trimmer head should reinstall normally with the correct mounting parts.

Q: What maintenance should I do after installing this gear head on my SRM-225U or SRM-280U?

After installation, make sure the gear head is aligned properly on the shaft, all fasteners are tightened to spec, and the cutting head spins smoothly without wobble. It is also a good idea to keep the gearbox properly greased at the recommended service intervals, because low grease is one of the main causes of premature gear head wear.

Compatibility

This part is verified to fit the following equipment. Always confirm the model number stamped on your machine before ordering.

Brushcutter Weed Eater Brush Cutter Part No. P021008182

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

  1. Measure shaft diameter. Common sizes are 24mm, 25.4mm, and 28mm — check your trimmer manual or measure the drive shaft.
  2. Count the splines. The gear head input must match your shaft spline count (typically 7 or 9).
  3. Check output thread. Verify the thread direction and size for your cutting attachment.
  4. 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.

Where to buy

This part is available through Amazon with free returns on most orders. We've verified the fitment listed above — check the live listing for current price, stock, and delivery options.

Check current price on Amazon

Affiliate disclosure: we may earn a commission when you purchase through this link, at no extra cost to you.

§ Compare

Similar Gear Heads

§ Guides

Related how-to guides