Usually vibration on ZIL-5301 is felt most at a speed of 60-70 km/h
If vibration occurs when driving ZIL-5301:

The coarse filter is designed to pre-clean the fuel from mechanical impurities and water and is located on the frame in front of the fuel tank.
Possible malfunctions and methods for their elimination D-245E3
If a malfunction occurs during the operation of the vehicle (lighting up, flashing the diagnostic lamp of the “Common Rail” system), it is necessary to diagnose the “Common Rail” system using the diagnostic lamp and the diagnostic key and eliminate the identified malfunctions. The blinking of the diagnostic lamp characterizes the occurrence of a more serious malfunction than its continuous burning.

Front wheel brake mechanisms of ZIL-5301
The design of the front wheel service brakes is shown in Fig. 1.
To remove the brake discs from the wheel hubs, unscrew bolts 1.

Many questions are asked about the installation of the wiring diagram of the ZIL Bychok turn signals.
That's why I had to cobble together a wiring diagram of the turn signals from the old wiring.