1. Product Advantages (Forever Seals Exclusive)
Caterpillar-Certified Compatibility: Meticulously engineered to match CAT-4C8253 specifications, ensuring 100% fit for Caterpillar machinery—no mismatches or performance gaps.
Durable Material: Made with high-grade nitrile rubber (NBR) by Forever Seals, resistant to oil, heat (up to 120°C/248°F), and hydraulic fluids, delivering 2x longer service life than generic O-rings.
All-in-One Convenience: Includes 15+ assorted O-rings (sizes below) + a precision installation tool, eliminating the need to source parts separately—saves 50% of maintenance time.
Cost-Effective: Reduces downtime by 30% (quick access to replacement parts) and cuts long-term repair costs vs. single-O-ring purchases.
2. Working Principle
O-rings in the CAT-4C8253 kit create a tight, pressure-activated seal between two mating surfaces (e.g., hydraulic valves, pneumatic cylinders). When compressed, the nitrile rubber deforms to fill gaps, blocking fluid/gas leakage. Forever Seals’ material ensures consistent elasticity even under cyclic pressure, maintaining sealing integrity for extended use.
3. Product Details
Packaging: Sturdy, labeled plastic case with size-divided compartments—prevents loss and enables quick size identification.
Tool Inclusion: Ergonomic silicone-grip O-ring pick tool (length: 12cm) for safe removal/installation, avoiding damage to seals or machinery.
Quality Assurance: Each O-ring undergoes 3-step testing (dimensional accuracy, elasticity, chemical resistance) by Forever Seals’ ISO 9001-certified facility.
4. O-Ring Sizes (Metric)
| CAT O-RING KIT 4C8253 |
| Ttem | NO | Specification | RTT |
| 1 | 8M8157 | 9.19x2.62 | 5 |
| 2 | 8M4437 | 13.94x2.62 | 10 |
| 3 | 8M4438 | 17.12x2.62 | 5 |
| 4 | 8M4389 | 20.29x2.62 | 5 |
| 5 | 8M8283 | 21.89x2.62 | 3 |
| 6 | 8M8515 | 32.99x2.62 | 5 |
| 7 | 8M4435 | 18.64x3.53 | 5 |
| 8 | 8M4445 | 21.82x3.53 | 5 |
| 9 | 8M4446 | 23.39x3.53 | 5 |
| 10 | 8M4988 | 24.99x3.53 | 5 |
| 11 | 8M4432 | 26.57x3.53 | 5 |
| 12 | 8M5248 | 28.17x3.53 | 5 |
| 13 | 8M5254 | 31.34x3.53 | 5 |
| 14 | 8M4987 | 32.92x3.53 | 10 |
| 15 | 8M5249 | 34.52x3.53 | 5 |
| 16 | 8M4986 | 37.69x3.53 | 10 |
| 17 | 8M4992 | 40.87x3.53 | 3 |
| 18 | 8M4443 | 44.04x3.53 | 3 |
| 19 | 8M5661 | 47.22x3.53 | 3 |
| 20 | 8M4436 | 50.39x3.53 | 3 |
| 21 | 8M5010 | 53.57x3.53 | 3 |
| 22 | 8M4390 | 56.74x3.53 | 3 |
| 23 | 8M5252 | 66.27x3.53 | 3 |
| 24 | 8M4990 | 15.24x5.33 | 3 |
| 25 | 1S0004 | 18.42x5.33 | 5 |
| 26 | 9H6067 | 21.59x5.33 | 5 |
| 27 | 9M4849 | 23.16x5.33 | 5 |
| 28 | 8M4991 | 27.94x5.33 | 3 |
| 29 | 9M7002 | 37.46x5.33 | 3 |
| 30 | 9M9647 | 40.64x5.33 | 3 |
| 31 | 2S2251 | 43.82x5.33 | 5 |
| 32 | 6L1651 | 50.17x5.33 | 3 |
5. Application Range
Exclusively for Caterpillar equipment, including:
Construction machinery (excavators, loaders: e.g., CAT 320, 966M)
Agricultural machinery (tractors, harvesters: e.g., CAT Challenger MT800)
Mining equipment (dump trucks, drills: e.g., CAT 793F)
Hydraulic/pneumatic systems in Caterpillar industrial engines
6. FAQ
Q1: Is this kit compatible with non-Caterpillar machinery?
A1: No—designed strictly for CAT models matching CAT-4C8253 specs; contact Forever Seals for custom kits for other brands.
Q2: How to store the kit for maximum O-ring life?
A2: Keep in a cool (15–25°C), dry place; avoid direct sunlight or contact with solvents.
Q3: Does Forever Seals offer a warranty?
A3: Yes—12-month warranty against material defects; free replacement if O-rings fail under normal use.
7. Forever Seals Selling Points
20+ years of expertise in industrial sealing solutions, specializing in Caterpillar aftermarket parts.
Global shipping with 48-hour dispatch for urgent maintenance needs.
Technical support team available 24/7 to assist with size selection or installation queries.