Shifting into gear issues

I drive an automatic V-6... whenever shifting from park to reverse for park to drive it's a hard shift… Feels like my transmission is going to fall off… Any suggestions on what to troubleshoot first? The truck has about 230,000 miles on it and the transmission was rebuilt around 170,000

 

Driveshaft U joints and center bearing for excessive play, maybe

 

I have a 2005 so second gen but I had this issue, the shifter would even slip into neutral while driving. I lubed up this piece in the side of the trans that connects the linkage to the trans. 2 years later she's perfect!

 

Center bearing is worn out… Probably explains why I have a little bit of a wobble as I get above 50 to 60 mph… I will work on replacing that first… I also did the same thing and lubed up the shifting moving parts next to the transmissions… Instead of lube or used silicone spray

 

Also, check your mounts for movement?