TO 00591-00439-81

Frequently Asked Questions

Q: What is the oil seal TO 00591-00439-81 and what does it seal?
A: The TO 00591-00439-81 is a Toyota OEM oil seal designed for axle housing sealing on electric lift trucks. It prevents differential or axle lubricant from leaking while containing contamination ingress. This seal is critical for drivetrain reliability.

Q: What are the dimensions of the TO 00591-00439-81 oil seal?
A: This seal measures 50 mm inner diameter, 70 mm outer diameter, and 9 mm width. These dimensions are precise and must match your axle housing bore exactly. Verify your truck model against the specification sheet before ordering.

Q: What material is the TO 00591-00439-81 oil seal made from?
A: The seal is constructed from nitrile butadiene rubber with a metal case. Nitrile rubber is selected for resistance to mineral oil exposure and temperature cycling in industrial lift truck environments. The metal case provides structural rigidity and press-fit retention.

Q: How do I diagnose a failed oil seal on my Toyota electric lift truck?
A: Signs of seal failure include oil leakage visible on the axle housing, lower than normal oil level in the differential, and contaminated axle fluid. Water in the oil indicates the seal is allowing external ingress. Replace immediately to prevent drivetrain damage.

Q: What is the lifespan of the TO 00591-00439-81 oil seal?
A: Oil seals typically last the full service life of the equipment if properly installed and maintained. Failure is accelerated by improper axle bearing preload, contaminated oil, and water ingress. Regular oil analysis and level checks extend seal life.

Q: Is this oil seal compatible with non-Toyota electric lift trucks?
A: This is a Toyota OEM part number. Do not assume it fits Crown, Raymond, Yale, or other brands without engineering verification. Axle housing geometry and seal bore specifications are manufacturer specific.