cought between clonks !!!

[chris5.2]

Hi , i need some help, i've posted the same mesage 2 months ago and the only answer i got was "ask dale" so dale feel free to coment ( please) . my gc 93 5.2 now has 99.k miles ( last time i posted had 93.k m. went to Manhathan and back plus some normal use ) and this is the problem :
accelerating the car goes fine ( may lack some power ) but when breaking from 20 mph to 15 it downshift with a clonk !! and at the same moment the rpms jump to 1000 , same times it dosn"t hapens but most of the time that is the way it work so i have to take my foot from the brake at the wright moment , say 16 mph , so the clonk !! is not so loud , this is realy anoying during rush hour , if you accelerete realy slowly you get a clonk !! too CLONK !! . please help .

[wheels4]

It could be your u/joint`s I would have them checked first.If they have never been replaced they are due.

[crude_ride]

Try checking your engine and transmission mounts. The touque from the transmission when it downshifts can cause everything to shift and bang against something.