I put a used tranny in over the weekend. It'* working fine thru the gears, just when I put the tranny into reverse on start up, it kinda bangs into reverse. No other harsh shifts anywhere, just a bang when putting in reverse. It'* a bit smoother after engine is warm. Any ideas what to check on this used tranny.

Is it a GoodWrench re-manufactured transmission from GM or one from a junkyard? What do you mean by bang? Does it make a loud Bang sound or does it hit hard when you shift it into reverse? I have a GoodWrench re-manufactured transmission in my '93 Eighty-Eight and it slams when I shift into reverse, when it'* cold.

It was a used unit from a junk yard. I seafoamed it, and changed fluid and filter....after about a day of use, it smoothed on out and has been running fine.

That'* cool. I'm glad the problem solved itself