Skip to product information
1 of 1

721-98-00600 Steering Cylinder Seal Kit For Komatsu HD785-7 | Ruijueparts

721-98-00600 Steering Cylinder Seal Kit For Komatsu HD785-7 | Ruijueparts

Regular price $23.88
Regular price Sale price $23.88
Sold out
15 people are viewing this right now

Availability2000 in stock

Volume discounts available · Minimum order quantities apply for bulk pricing

Contact for Quote
SKU: 721-98-00600
Vendor: RuiJueParts

Shipping & Returns

Shipping:
- Standard models take 1-3 business days.
- Bulk orders take 3-7 business days.
- For urgent orders, please contact our sales team. [Email: info@ruijueparts.com]

Returns:
We accept returns within 30 days of purchase. Learn more—return policy

Packaging details

PP bag, carton

Place of Origin

China

Payment terms

L/C, T/T, Western Union, MoneyGram

Performance

Oil Sealing

View full product details

Product Description

The aftermarket 721-98-00600 steering cylinder seal kit is referenced for verified Komatsu HD785-7 off-highway dump truck steering-cylinder service. It supports seal replacement when cylinder leakage or internal sealing wear is found during heavy-duty truck maintenance. This part should be identified by the part number and the installed steering cylinder, not by a general “Komatsu seal kit” search. Public listings can contain conflicting machine claims, so Ruijueparts recommends confirming the truck serial number, steering-cylinder reference, and old-kit number before ordering. B2B buyers may submit a purchasing list for reference checking.


Item specifics

Part Number: 721-98-00600
Fits Models: HD785-7 
Brand: Komatsu replacement
Type:

Steering Cylinder Seal Kit / Hydraulic Cylinder Seal Kit

Application:
  • Designed for verified hydraulic steering-cylinder maintenance on Komatsu HD785-7 off-highway dump trucks. The steering cylinder moves the steering linkage to turn the truck’s wheels during hauling, maneuvering, and site operation.
  • Dump Truck: HD785-7 
Size: Standard Size


FAQ

  • Q1: What is Komatsu 721-98-00600 used for?
    A: It is referenced as a steering-cylinder seal kit for the Komatsu HD785-7 off-highway dump truck.
  • Q2: Does 721-98-00600 fit Komatsu PC200 excavators?
    A: We do not recommend listing or ordering it for PC200 models based only on generic online listings. The stronger available references identify it with the HD785-7 steering-cylinder application.
  • Q3: Is this a seal kit for every hydraulic cylinder on the HD785-7?
    A:
    No. It is specifically associated with steering-cylinder service. Hoist, suspension, brake, and other hydraulic cylinders may require different repair kits.

Why choose Ruijueparts

Lower cost — honest trade-off

Our aftermarket seal kits deliver a practical, cost-effective solution without compromising on real-world performance. We offer a lower upfront cost and reliable sealing for your daily maintenance and repair needs.

Extensive part number range

We stock seal kits across CAT, Komatsu, Volvo, JCB, Hitachi, Doosan, John Deere, Kubota, and 10+ other brands—one supplier for your whole fleet.

Flexible packaging options

Ship under RuijueParts branding, neutral (unbranded) packaging, or your own private label. Suitable for resellers and distributors.

Customization Service

When genuine OEM seals are out of production for your old machinery, we can custom-make oil seals using your dimensions or our engineer-recommended specifications.

Wholesale & OEM bulk orders

Ship under RuijueParts branding, neutral (unbranded) packaging, or your own private label. Suitable for resellers and distributors.

Warranty on request

Volume pricing for repair shops, dealers, and fleet operators. Get a quote via our website or WhatsApp: +86 13692100161.

When budget aftermarket makes sense

OEM seal kits are the right choice when machinery is under active warranty, operating at peak duty cycles, or when failure risk is unacceptably high. Budget aftermarket—like Ruijue Parts—makes sense in these common scenarios:

Older or end-of-life equipment

When a machine is aging out of your fleet, OEM parts cost more than the job warrants. A budget kit extends service life without over-investing.

Secondary or backup machines

For machines used infrequently or on lower-intensity tasks, premium OEM pricing may not be justified.

OEM parts unavailable or on long lead time

When OEM stock is out or delivery takes weeks, an available aftermarket kit gets your machine running now.

Fleet maintenance on a fixed budget

Repair shops and fleet managers running high volumes of machines often balance OEM and aftermarket across their portfolio based on criticality.

Installation guide

1. Depressurize the hydraulic system

Fully retract the cylinder and relieve system pressure before disassembly. Never work on a pressurized circuit.

2. Remove and disassemble the cylinder

Remove from the machine. Unthread the gland nut and withdraw the piston rod carefully to avoid surface damage.

3. Clean all components thoroughly

Clean the bore, rod, and all metal parts with a lint-free cloth. Contamination introduced during reassembly accelerates seal wear—this step is especially important for budget-grade seals.

4. Inspect the rod and bore

Check for scoring or pitting. Budget seals are more sensitive to surface imperfections—address rod damage before fitting new seals.

5. Install the seal kit

Lightly coat each seal with clean hydraulic fluid before installation. Use proper seal drivers — not screwdrivers or sharp tools — to avoid nicking the sealing lip.

6. Reassemble and pressure test

Torque the gland nut to spec and cycle the hydraulic system under no-load conditions. Inspect for leaks before returning the machine to service.

Maintenance tips

Inspect every 250–500 hours

Budget-grade seals may have shorter service intervals than OEM. Inspect rod seals for moisture, oil film, or weeping more frequently and replace proactively.

Keep hydraulic fluid clean

Contaminated fluid degrades seals faster — this applies especially to non-OEM materials. Replace fluid and filters on schedule.

Protect exposed rod surfaces

When storing equipment with cylinders extended, protect rod surfaces from corrosion and debris to preserve wiper seal life.

Ensure Proper Installation

Avoid using sharp tools during assembly to prevent nicks or scores on the seal lips. Pre-lubricating all components with clean hydraulic oil is recommended to ensure a smooth fit into the cylinder grooves.

Reduce Downtime with Reliable Seals.

Click "Add to Cart" for immediate dispatch, or contact our team for bulk pricing and wholesale support.

1 of 5