I am not sure what you mean when you say there is a slow drag when in drive but if you don't have forward gears this is most likely low fluid or a valve body issue. There is a chance that there is a cut seal inside the unit but let's start with the fluid.
Check the level and condition of the fluid and if it is low, top it off and let's see if that restores forward gears. If it does, then we need to service the unit.
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Wednesday, March 17th, 2021 AT 4:17 PM