More photos Toyota ist
2003 Toyota ist o/d problems
| Date: | February 17, 2010, 10:35 am | |
| Name: | Liilan | |
| Location: | Kenya, Nairobi | |
| Vehicle: | Toyota ist | |
| Year: | 2003 | |
| Problems: | I would like to understand how the Overdrive (O/D) works. Is fuel consumption lower when overdrive is on or off? Thank you. | |
| Contact: | show contact |
Suggest a Solution
| October 14, 2010, 5:14 am from: Ernest |
| Generally speaking, overdrive (OD) is the highest gear in the transmission. Overdrive allows the engine to operate at a lower rpm for a given road speed. This allows the vehicle to achieve better fuel efficiency, and often quieter operation on the highway. When it is switched on, an automatic transmission can shift into overdrive mode after a certain speed is reached (usually 70+ km/h [43+ mph] depending on the load). When it is off, the automatic transmission shifting is limited to the lower gears. For an automatic transmission, it is almost always best to select overdrive and allow the transmission to control engagement of the overdrive. (It may be necessary to switch it off if the vehicle is being operated in a mountainous area or when towing a trailer.) With a manual transmission, overdrive should usually be selected when the average speed is above 70 km/h (approx. 43 mph). The overdrive consists of an electrically or hydraulically operated epicyclic gear train bolted behind the transmission unit. It can either couple the input driveshaft directly to the output shaft (or propeller shaft) (1:1), or increase the output speed so that it turns faster than the input shaft (1:1 + n). Thus the output shaft may be "overdriven" relative to the input shaft. In newer transmissions, the overdrive speed(s) are typically as a result of combinations of planetary/epicyclic gearsets which are integrated in the transmission. In these cases, there is no separately identifiable "overdrive" unit. A number of such transmissions and transaxles are manufactured by Aisin, for use in vehicles produced by many different manufacturers. In older vehicles, it is sometimes actuated by a knob or button, often incorporated into the gearshift knob, and does not require operation of the clutch. Newer vehicles have electronic overdrive in which the computer automatically adjusts to the conditions of power need and load. |
| Contact: show contact |
| November 24, 2010, 6:17 pm from: Dr. Md. Rizaul kabir |
| if you drive below 70km/hr , please keep the ``OD off`` display on the screen by pressing the small button in gear button. if you drive above 70km/hr , then press the small button in gear button to disappear the ``OD off`` display on the screen. |
| Contact: show contact |
Updated on April 16, 2024