99 ford ranger
So my 1999 ford ranger 4.0 engine 4x4 started
slipping going into 3rd. I thought it would go away
but then later on it started slipping going into 2nd. I
changed the filter, fluid and gasket on the
transmission. After I did that I took it for a drive and
it stopped slipping into 2nd but still slips going into
3rd. When I changed the fluid and filter there were
no metal or brass chips in the pan. Any ideas what I
need to do to fix?