Table of contents: Fluid leakage 🠇 Transmission fluid brown, or has…🠇 General gear selection problems 🠇 Transmission will not downshift…🠇 Engine won't start in any gear, or…🠇 Transmission slips, shifts roughly,…🠇
Note: Due to the complexity of the automatic transmission, it is difficult for the home mechanic to properly diagnose and service this unit. For problems other than the following, the vehicle should be taken to a dealer service department or automatic transmission specialist. Don't be in a hurry to remove the transmission if a fault is suspected, as most testing is carried out with the unit still fitted.
Fluid leakage
- Automatic transmission fluid is usually dark in colour. Fluid leaks should not be confused with engine oil, which can easily be blown onto the transmission by airflow.
- To determine the source of a leak, first remove all built-up dirt and grime from the transmission housing and surrounding areas using a degreasing agent, or by steam-cleaning. Drive the vehicle at low speed, so airflow will not blow the leak far from its source. Raise and support the vehicle and determine where the leak is coming from. The following are common areas of leakage:
a) Fluid pan or "sump" (Chapter 1 and 7B).
b) Dipstick tube (Chapter 1 and 7B).
c) Transmission-to-fluid cooler pipes/unions (Chapter 7B).
Transmission fluid brown, or has burned smell
- Transmission fluid level low, or fluid in need of renewal (Chapter 1A).
General gear selection problems
- Chapter 7B deals with checking and adjusting the selector cable on automatic transmissions. The following are common problems which may be caused by a poorly-adjusted cable:
a) Engine starting in gears other than Park or Neutral.
b) Indicator panel showing a gear other than that being used.
c) Vehicle moves when in Park or Neutral.
d) Poor gear shift quality or erratic gear changes.
- Refer to Chapter 7B for the selector cable adjustment procedure.
Transmission will not downshift (kickdown) at full throttle
- Low transmission fluid level (Chapter 1A).
- Incorrect selector cable adjustment (Chapter 7B).
Engine won't start in any gear, or starts in gears other than Park or Neutral
- Incorrect starter/inhibitor switch adjustment (Chapter 7B).
- Incorrect selector cable adjustment (Chapter 7B).
Transmission slips, shifts roughly, is noisy, or has no drive in forward or reverse gears
- There are many probable causes for the above problems, but the home mechanic should be concerned with only one possibility - fluid level. Before taking the vehicle to a dealer or transmission specialist, check the fluid level and condition of the fluid as described in Chapter 1A. Correct the fluid level as necessary, or change the fluid and filter. If the problem persists, professional help will be necessary.