REF•14 Fault Finding
Manual transmission
Noisy in neutral with engine running
mm Mainshaft bearings worn (noise apparent with clutch pedal
released, but not when depressed) (Chapter 7, Part A).*
mm Clutch release bearing worn (noise apparent with clutch pedal
depressed, possibly less when released) (Chapter 6).
Noisy in one particular gear
mm Worn, damaged or chipped gear teeth (Chapter 7, Part A).*
mm Worn bearings (Chapter 7, Part A).*
Difficulty engaging gears
mm Clutch fault (Chapter 6).
mm Worn or damaged gear linkage (Chapter 7, Part A).
mm Worn synchroniser assemblies (Chapter 7, Part A).*
Vibration
mm Lack of oil (Chapter 1).
mm Worn bearings (Chapter 7, Part A).*
Jumps out of gear
mm Worn or damaged gear linkage (Chapter 7, Part A).
mm Worn synchroniser assemblies (Chapter 7, Part A).*
mm Worn selector forks (Chapter 7, Part A).*
Lubricant leaks
mm Leaking differential side gear oil seal (Chapter 7, Part A).
mm Leaking gearchange shaft or speedometer pinion oil seals (Chap-
ter 7, Part A).
mm Leaking housing joint (Chapter 7, Part A).*
mm Leaking mainshaft oil seal (Chapter 7, Part A).*
* Although the corrective action necessary to remedy the symptoms
described is beyond the scope of the home mechanic, the above
information should be helpful in isolating the cause of the condition, so
that the owner can communicate clearly with a professional mechanic.
Automatic transmission
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.
Fluid leakage
mm 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.
mm 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) Transmission oil sump (Chapters 1 and 7, Part B).
(b) Dipstick tube (Chapters 1 and 7, Part B).
(c) Transmission-to-fluid cooler pipes/unions (Chapter 7, Part B).
(d) Speedometer drive pinion O-ring (Chapter 7, Part B).
(d) Differential side gear oil seals (Chapter 7, Part B).
Transmission fluid brown, or has burned smell
mm Transmission fluid level low, or fluid in need of renewal (Chapter 1).
Transmission will not downshift (kickdown) with
accelerator pedal fully depressed
mm Low transmission fluid level (Chapter 1).
mm Incorrect kickdown cable adjustment (Chapter 7, Part B).
mm Incorrect selector cable adjustment (Chapter 7, Part B).
mm Engine management system fault (Chapters 1, and 4).
General gear selection problems
mm Chapter 7, Part B, 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 on gear selector lever pointing to a gear other than
the one actually being used.
(c) Vehicle moves when in Park or Neutral.
(d) Poor gear shift quality or erratic gear changes.
Refer to Chapter 7, Part B for the selector cable adjustment
procedure.
Engine will not start in any gear, or starts in gears
other than Park or Neutral
mm Incorrect selector cable adjustment (Chapter 7, Part B).
mm Incorrect starter inhibitor switch adjustment (Chapter 7, Part B).
Transmission slips, shift roughly, is noisy, or has
no drive in forward or reverse gears
mm 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 1. Correct the fluid level as necessary, or
change the fluid if needed. If the problem persists, professional help
will be necessary.
Driveshafts
Clicking or knocking noise on turns (at slow speed
on full-lock)
mm Lack of constant velocity joint lubricant (Chapter 8).
mm Worn outer constant velocity joint (Chapter 8).
Vibration when accelerating or decelerating
mm Worn inner constant velocity joint (Chapter 8).
mm Bent or distorted driveshaft (Chapter 8).
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