Possible causes of knocking noise when shifting the Ford Focus 2 automatic transmission:
1. Worn or damaged gears:
* Gears can wear out over time or under excessive load, causing a knocking noise when shifting gears.
2. Low transmission fluid level:
* Insufficient fluid levels can result in insufficient lubrication and abrasion of internal components, causing knocking noises.
3. Contaminated transmission fluid:
* Contaminated fluid can clog the hydraulic unit and solenoids, what??? knock
4. Worn or damaged torque converters:
* The torque converter smoothes the transfer of torque from the engine to the transmission. Wear or damage may cause a knocking noise.
5. Faulty solenoids:
* Solenoids control the flow of fluid within the transmission. Faulty solenoids can cause harsh shifting and knocking noises.
6. Faulty hydraulic unit:
* The hydraulic unit controls the fluid pressure in the transmission. A faulty unit may create a knocking noise.
7. Worn or damaged engine or transmission mounts:
* Worn mounts can allow the engine or transmission to shift when changing gears, causing a knocking noise.
8. Faulty Transmission Control Module (TCM):
* The TCM controls the operation of the transmission. A faulty TCM can cause rough shifting and knocking noises.
Solution
Diagnosing and eliminating the cause of the knocking requires professional knowledge and tools. It is recommended that you contact a qualified mechanic for:
*Checking the level and condition of transmission fluid
* Diagnose faults using OBD scanner
* Repair or replace damaged components
* TCM programming if necessary