Possible causes of impact when engaging reverse gear on a Ford automatic transmission:
1. Low transmission fluid level:
* Check the transmission fluid level. If there is insufficient fluid, insufficient lubrication will occur and shock loads will be transferred to the gearbox.
2. Reverse solenoid faulty:
* The reverse gear solenoid controls the engagement of the corresponding gear. A faulty solenoid can cause a delayed or harsh transmission to engage.
3. Worn friction discs:
* Friction discs wear out over time, and their condition affects the smoothness of gear engagement. Worn discs can slip, causing shock.
4. High pressure pump malfunction:
* The high pressure pump provides fluid pressure for gear shifting. A faulty pump can result in insufficient pressure, making shifting difficult.
5. Valve block clogged:
* The valve body controls the fluid flow in the gearbox. A blockage can interfere with fluid flow and cause shock.
6. Malfunction of the transmission control module (TCM):
* The TCM controls the operation of the automatic transmission. A faulty TCM can cause the transmission to shift incorrectly.
7. Wiring problems:
*Electrical problems can affect transmission control, causing knocks.
Diagnostics and repair:
* Start by checking the fluid level.
*Then use a scan tool to read the trouble codes from the TCM.
*Also inspect friction discs, solenoids and other mechanical components for wear or damage.
* Replace or repair faulty components according to the fault.
* It is recommended that you consult a qualified mechanic before performing any repairs.