Okay. More than likely this is inside the transmission. The low/reverse clutch is applied in reverse and first and is most likely your issue. However, this is a 62TE transmission and they are pretty cheap to replace. They have been around since the 1990's so most shops can rebuild them also pretty easily.
If you have not changed the fluid in a while, you can try this but it sounds like it is just beginning to wear out.
If it were me and being familiar with these 62TE units, I would change the fluid and then just keep driving it until it is missing shifts or slipping/banging and then rebuild it.
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Saturday, June 29th, 2019 AT 6:35 PM