Overview
| MLIT filing number | 1139000 |
|---|---|
| Type | Statutory Recall (government-mandated recall) |
| Date filed | October 18, 2016 |
| Manufacturer(s) | Hino |
| Component | Manual Transmission |
| Production period | May 2012 — August 28, 2014 |
| Vehicles affected | 851 units |
Defect
On large buses equipped with an electrically controlled air-shift transmission, the end-face geometry of the outer piston — which switches between even and odd gear ranges in the shift unit — is improper, resulting in insufficient surface area exposed to air pressure. This causes a delay in outer piston actuation during gear changes. The outer piston then moves abruptly, accelerating wear on the cup seals of both the outer and inner pistons, compromising air tightness and prolonging shift time. Continued use may, in the worst case, result in the inability to shift gears, rendering the vehicle inoperable.
Corrective action
On all vehicles, replace the complete piston assembly in the shift unit with corrected parts.
Affected models & chassis ranges
This filing lists 3 type code(s). A vehicle is affected if its chassis number falls within one of the ranges below.
| Type code (型式) | Model | Chassis ranges |
|---|---|---|
| QRG-RU1ASCA | SELEGA | RU1ASC-40011 — RU1ASC-40863 |
| QRG-RU1ASCA改 | SELEGA | RU1ASC-40011 — RU1ASC-40863 |
| QTG-RU1ASCA | SELEGA | RU1ASC-40011 — RU1ASC-40863 |
Original Japanese (MLIT source text)
Show the original Japanese filing text
状況
大型バスの電気エア切り替え式トランスミッションのシフトユニットにおいて、偶数段と奇数段を切り替えるアウターピストンの端面形状が不適切なため、エア圧を受ける面積が不足し、切り替え時にアウターピストンの作動開始が遅れることがある。そのため、アウターピストンが急速に動きアウターピストンとインナーピストンのカップシールが摩耗してエアの気密が保たれず変速時間が長くなり、そのまま使用を続けると、最悪の場合、変速ができず走行不能になるおそれがある。
改善措置
全車両、シフトユニットのピストン一式を対策品に交換する。
Source & verification
This entry reproduces public data from Japan's MLIT recall registry. English text is jdmvin.com's own translation; always verify against the official source:
https://renrakuda.mlit.go.jp/renrakuda/ris-detail-car.html?class=recalldatacar&id=3003867