New 4K0684 Washer Replacement suitable for Caterpillar Equipment
- New Washer Replacement suitable for Caterpillar Equipment
- Made to USA Specification
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Description for 4K0684 Washer
â–¶Specification for 4K0684 Washer
â–¶Exact Fit Guarantee for 4K0684 Washer
â–¶| Dimensions | 2.05x2.05x0.24 |
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Quick and prompt support. Easy to work with. They had the parts in stock which is even better. Great pricing.
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Customer service was excellent today! I have never had a company go behind the scenes to see what was happening with my payment error and resolve it so I could complete my order without having to do it all over again. Hats off to Propel Parts!
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Quick and efficient.
Great products and a great team to deal with. We had a small issue with a missing part and the Customer Services Team dealt with it quickly and efficiently and in a way which left me, the customer, feeling entirely satisfied. Would highly recommend. -
The customer care response was very awesome. It was more than what I expected
The customer care response was very effective and timely
The response time was amazing
The availability of most of the parts that I wanted was also very awesome
Thanks keep it up -
Excellent experience.
Mike has been very helpful. I am looking forward to keep doing business with them
Frequently Asked Questions
What is the Caterpillar 4K0684 washer used for?
The 4K0684 washer is a standard hardware component used throughout Caterpillar equipment to distribute fastener load, protect mating surfaces, and maintain proper joint preload in bolted connections across engine, structural, and attachment assemblies.
What type of washer is the 4K0684?
The exact washer profile ??? flat, lock, sealing, or hardened ??? is specified in the product listing. Always use the washer type designated in the service manual for the specific joint to ensure the correct load distribution and sealing performance.
Is this washer compatible with multiple CAT models?
Yes ??? the 4K0684 is used across numerous Caterpillar equipment families. Verify the part number against your machine's documentation before placing an order. Check your manual or reach out to Propel Parts for help verifying fitment.
Can I replace this washer with a standard hardware store equivalent?
Caterpillar-specified washers are selected for specific dimensions, hardness, and tolerances that standard hardware store stock may not match. For critical joints, use the exact specified part. In low-load, non-critical applications, an equivalent may be acceptable ??? but when in doubt, use the OEM-specified part.
Should washers be inspected during routine maintenance?
Yes ??? inspect washers for signs of deformation (particularly hardened and spring washers), corrosion, cracks, or embedding into the mating surface. A washer that no longer provides a flat, undamaged bearing surface should be replaced to maintain proper joint integrity.
Are bulk quantities available for fleet maintenance?
Propel Parts stocks a wide range of Caterpillar-compatible hardware suitable for fleet programs. Browse our hardware parts for heavy machinery for washers, bolts, and other fastening components in the quantities your operation needs.
What warranty is offered on the 4K0684 washer?
All Propel Parts hardware carries a 1-year warranty against material and manufacturing defects. Same-day weekday shipping and a no-hassle 30-day return policy are standard on all orders.

We know equipment downtime costs money, so fast and reliable shipping is a priority at Propel Parts. Orders placed on weekdays before 3:00 PM ET typically ship the same day, with expedited delivery options available for many locations when time is critical.
We ship across the U.S., Canada, and over 130 countries worldwide, helping customers keep machines running wherever they operate. Available shipping methods and delivery estimates are shown at checkout so you can select the option that best fits your timeline.
Tracking information is emailed within 24–48 hours after your order is processed, giving you full visibility from dispatch to delivery and peace of mind that your parts are on the way.

Our refund policy is simple. We offer a 30-day, no-hassle return policy, and we make every effort to provide the best service and highest-quality parts possible. If you’re not fully satisfied with your purchase, you may return it within 30 days for a refund. Full details are available on our Returns Policy page.

Buy with confidence. All parts from Propel Parts are covered against material or manufacturer defects for 12 months from the original invoice date. We stand behind every part we sell, so you can count on reliable performance and dependable support. Full details are available on our Warranty Policy page.
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