I have just done a complete rebuild on the automatic transmission. I used a OEM Banner kit. I have replaced all of the seals all of the clutch plates and installed a transgo valve upgrade. The car had a cracked A drum and a bad bearing behind the C drum. Both wich were also replaced. After the rebuild the car was running great for the first 100 miles. Now it has a hard kick down into first gear when driving. Excellerating up to speed and out of no where it will kick down HARD into first. It will hold first for a few seconds and then release start acceleration again and do another hard kickdown and hold first for a minute. Any ideas on what is going on here??