Step-by-Step: How to Measure Bucket Pins & Bushings

Step-by-Step: How to Measure Bucket Pins & Bushings

Step-by-Step: How to Measure Bucket Pins & Bushings (Excavator Measurement Guide)
Accurate measuring techniques for excavator bucket pins and bushings. Includes diameter, length, tolerance tips & printable measurement guide.

When it comes to excavator maintenance or ordering replacement parts, few things matter more than correctly measuring your bucket pins and bushings. Even a few millimeters of difference can cause premature wear, misalignment, or major fitment issues. The good news? With the right tools and a clear process, anyone can measure bucket pins confidently and accurately.

Below is a simple, step-by-step guide to help you determine pin diameter, pin length, bushing size, fit tolerances, and more—along with practical tips and a measurement chart you can reference anytime.

Why Correct Measurement Matters

Bucket pins and bushings serve as the pivot points for your bucket, H-Link, and cylinders. When these parts don’t match OEM dimensions:

  • Pins won’t seat properly
  • Excess movement increases wear
  • Bushings fail prematurely
  • Grease passages may not align
  • Components may seize or oval out

Taking a few extra minutes to measure ensures you choose the correct pin size, extend component life, and avoid costly downtime.

Tools You’ll Need

To measure bucket pins and bushings accurately, grab:

  • Digital calipers (preferred)
  • Tape measure
  • Micrometer (for precision checks)
  • Straightedge or flat surface
  • Cleaning rag
  • Light source

If the pin or bushing is rusty, a quick cleaning helps get more accurate readings.

How to Measure Pins

1. Measure Pin Diameter

This is the most important measurement.

  • Use digital calipers
  • Measure at multiple points along the pin (to spot tapering or wear)
  • If the readings vary, use the largest diameter

Tip: OEM bucket pins are usually round, but worn pins often become oval. If yours is oval, you must replace it.

2. Measure Overall Pin Length

Also called excavator pin length, this measurement determines whether the pin will sit correctly through the bucket ears.

  • Lay the pin on a flat surface
  • Measure end-to-end
  • Include any collars, grease grooves, or flanges

Incorrect pin length can prevent proper tightening or allow excessive side play.

3. Measure Shoulder or Flange Width (if applicable)

Some pins have:

  • Welded collars
  • Bolt-on retainers
  • Integrated shoulders

Measure the width and position of these features, as they're critical for alignment.

4. Check the Grease Passage Location

Pins may include:

  • Grease holes
  • Annular grooves
  • Fittings

Snap a quick picture or measure the distance of the grease hole from the end of the pin. Grease alignment ensures your bushings stay lubricated.

How to Measure Bushings (Size Guide)

Bushings are just as important as pins. To determine bushing size:

1. Measure Outside Diameter (OD)

  • Use calipers
  • Measure at multiple points to check for roundness

2. Measure Inside Diameter (ID)

  • This tells you the required pin size
  • New bushings have strict ID tolerances, use a micrometer if possible

3. Measure Bushing Length

  • Measure end-to-end
  • Verify both bushings on the same ear match in length

4. Check Flanges (If Present)

Some bushings have a flange on one side. Measure:

  • Flange diameter
  • Flange thickness

Pro Tip:

If your bushing ID is significantly larger than your pin diameter, you likely have wear, not a mismatch. Replace both together for the best results.

How to Choose the Correct Pin Size

When ordering replacement pins and bushings, confirm:

  1. Machine make & model
  2. Pin diameter
  3. Pin length
  4. Bushing ID/OD
  5. Ear spacing (distance between bucket ears)
  6. Bolt-on or collar style

Mixing aftermarket and OEM dimensions can lead to fitment issues, accurate measurement ensures you're installing parts that match OEM specs.

Final Thoughts

Learning how to measure bucket pins and bushings properly helps prevent premature wear, ensure proper bucket fitment, and save you money in the long run. With the steps above, you can confidently measure your components and choose the right replacement parts every time.