Make sure the fluid level is correct. Also check it for trouble codes with an OBD reader.
There are several things that can go wrong on automatic trannys.
Pressure in the tranny is low, shift module, etc.
The only way to track these things down as they are electro-mechanical is trouble codes or start replacing parts by process of most likley failed part, which is hard to do. So, getting the trouble codes is important. The fact thatit is modified will also make diagnosis tough as there may besome component that does not work well with some stock somponent.
The high temperature is a really bad sign as the transmission is so hot that it is overheating the engine coolant from the tranny cooler which runs through the radiator.
Whatever you do, do it quick and DO NOT drive the car if the temperature gets near the hot mark. You will damage the motor.
My first instinct is that the transmission needs to be torn down from the symptoms you desribe.
Automatic transmissions are not easy to work on and should only be serviced by a qualified transmission shop as many special tools are needed as well as experience.
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Friday, September 23rd, 2011 AT 12:32 AM