Toyota HiAce: Steering Box Input Shaft Oil Seal Leak

The KDH200 HiAce uses a hydraulic power-assisted recirculating ball steering box mounted on the chassis rail. The input shaft oil seal, which retains hydraulic fluid around the shaft where the steering column enters the box, degrades with heat cycling and age. As the seal deteriorates it allows power steering fluid to weep past the shaft and pool on the chassis or drip onto the exhaust. Progressive fluid loss reduces hydraulic assist, and in neglected cases the pump runs dry causing pump cavitation and failure in addition to the original seal fault.

• Power steering fluid puddle or staining on the ground under the front-left of the vehicle
• Power steering reservoir requiring topping up more frequently than normal
• Groaning or whining from the power steering pump under full lock indicating low fluid
• Visible reddish-brown fluid residue on the steering box casing or chassis rail

1. 1

   Check the power steering fluid reservoir level and note any reddish or amber ATF-type fluid staining on the chassis rail below the steering box.

2. 2

   With the engine running, have an assistant turn the wheel lock to lock while you observe the input shaft with a torch — active weeping confirms the seal has failed.

3. 3

   Inspect the steering box casing for cracks or seam leaks that indicate a more extensive rebuild is needed.

Parts involved: Steering rack, Chassis and structural rust.

$380 to $2,800 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

• “Has the power steering fluid reservoir been topped up recently?”
• “Is there any staining or wet residue visible on the chassis under the steering box?”
• “Has the steering ever groaned or felt heavy at low speed?”

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.