Causes of vibration can be many. In the car there is a linked chain: engine – clutch – transmission – RK – connecting universal joints – drive axles – wheels – tires. The malfunction of any of these units or parts may cause vibration.
Engine. Due to its malfunction vibration can occur for several reasons. First, malfunction of the ignition system, in which disrupted the normal work cycle of the piston. This causes the vibration of the engine transmitted to all the units and through the motor mount to the frame and the car body. To eliminate this problem you need to adjust the ignition system of the vehicle. If there is a need to change the plugs and wires. Secondly, weakening the engine mounts. In this case, you must check the condition of fixing, and fix the defect.
Gear shift (transmission). Most often, the vibration can occur due to faults that occur mostly in the support shaft connecting the PPC and the RK. You need to check the wear of the shaft bearings and the gearbox. If there is a defect to replace. Also check up reliability of fastening of the checkpoint, make a broach.
Transfer box (RK). It was the turn of her checking for signs of vibration. If the box was removed for repair or for its diagnostics, check – not out (perhaps biased) point of installation, its installation. You can try to adjust the vertical position of the RK by putting the shims between the subframe and its mounts. Now check the wear of the flanges and the slotted part of the gimbal, especially in connection with the rear axle.
Different. The source of the vibration "Fields" can be slight, trivial damage to a propeller shaft on an obstacle. To check the shaft for bend, spin it in the lathe centers and find the deviation from the axis of rotation with the indicator. However, before doing all this, eliminate the visible reasons:
1. check and, if necessary, perform the wheel balancing of the vehicle;
2. check the continuity of the cord tire. If you have even a discreet "hernia" will be felt a decent vibration. Of course, if detected the tyre should be replaced.