Loss of any fo the gears ??
If you got all gears engaging, I'd say previous owner got the tv cable out of adjustment. My advise is that you take it to a competitive transmission shop and have them set it using pressure gauges as it should be done. A lot of people might tell you that it's self-adjustable if you push it all in. It's not. It has to be set, period. You can guess at it but if you get it wrong, get ready for a transmission rebuild.
The same goes for a rebuilt transmission. If you don't set the TV cable right and the transmission fails, you are out of luck.