Transmission shudder is usually caused by a lack of transmission fluid or a slipping torque converter clutch. Contaminants in the transmission fluid may also lead to transmission shudders, but because the transmission is a closed system, dirty transmission fluid is usually a sign of a larger problem.
It is usually a good idea for drivers to get their automobile to a mechanic if the transmissions begins shuddering, but there are some things they can check at home. If the vehicle shudders and over heats, this may be a sign of the torque converter going out. Overheating is also a sign of low transmission fluid.
Transmission shuddering combined with transmission slippage may be a sign that too little or too much fluid is making its way to the transmission. This is usually a telltale sign that the torque converter is failing.
Drivers with mechanical know-how may want to check the vehicle's EPR solenoid if transmission shudders are a problem. A quick adjustment of the EPR may fix the issue.
There are tons of quick-fix products on the market that claim to take care of transmission shudders simply by adding one of them to the transmission fluid. These products should be avoided because they only provide a temporary fix. Drivers should get to the root of the problem as soon as possible.