transmission problems

As of last week I started to notice very strange sounds coming out of the transmission. When you break and the car shifts down to the first gear, there’s a loud thud. At first I thought that the u joints are bad or need to be lubricated – unfortunately a solid greasing didn’t help at all. Anyone else get the thud when decelerating? This is very annoying and doesn’t sound good. I have over 50k miles on the car and it has been serviced at 15, 30 and 45k. Do you guys have any ideas what could be wrong with it?

Firstly the trannies are noisy and at the last downshift can make some noise... However I believe you have the same problem. First I had the band applied solonoid replaced. Wasn't that. As it turned out it was the U-joints and splines. As my guy told me the tolerances are way to tight. He replaced them and it went away but it is kinda of coming back...really a drag. They did it under warranty- My understanding is the U-joints and splines have to have play in them to work correctly. Good luck, and keep me posted