go ahead and do a drain and fill yourself, shouldnt need a full flush. worst case, you will end up with cleaner fluid. if the transmission filter wasnt changed, change that as well. just need a filter kit. inexpensive, comes with the tranny pan gasket, and easy to do. The shudder could be caused by the fluid. there was another thread that talked more about it. if the filter was already changed at 230k, then just do a fluid drain and fill. most people do that every 30k miles. Use a good brand of oil. In my manual, quality of oil makes a big difference. store brand sucked. id imagine its the same with autos.
2002 GT 5sp. 16x,xxx miles
Steeda Exhaust, C&L plenum, BBK Throttle Body, Steeda Underdrive, Steeda short throw, unknown stage clutch. Rear main leak. Compressor seal leak. Steeda lower control arms. good tires.