3500 Trans question
 

Hello all! Question about my Trans is when shifting into overdrive or fifth gear ( don't know the correct term) my rpms will jump a couple hundred like it is gonna downshift or slipping maybe. Is this normal for these transmissions or something I should worry about. Every gear grabs fine and isn't hard shifting at all. When driving like a grandma and it up shifts I get a shimmy which is front end related I believe but it's been cold so I haven't messed with it.
I've read alot people like the pcm upgrades since it changes the shift points and ect. soI was looking for similar experiences. Thanks in advance!