hello all i have a 04 pontiac sunfire with the 4T40E 4 speed automatic i recently put on a tsudo 4.2.1 header with a magnaflow high flow catalitic converter i realized i had missed tightening 2 bolts on my exhaust so i lifted the car high enough on one side for me to fit under and fix the problem. after lowering the car back down and driving for a while i noticed that when i shift from park to reverse there is a noticeable grinding noise coming from the transmission area all other gears shift great while goin down the road and all fluids are at there correct levels so i ask have any of you had this problem and know what to fix or is it all in my head