1995 sportage auto transmission

[outback]

my sportage auto changes down and then back to d. for no reason
when iam just driving along normal it will do this 4 or 5 times then it may
not do it again for weeks on end.
i have checked the diagnostic there fine. i have done a stall test it reads
out at 2.000rpm in all gears so that`s fine.
any helpers out there i will listen to any suggestion.
the car it`s self is running great the wiffy loves it.
help:

[cjmck422]

Just a few suggestions, first check the fluid level and condition. Having too much or too little fluid can create shifting problems. If the fluid is dark reddish-brown or even brown with a burnt smell, run a cleaning solvent through the transmission, then flush and replace the fluid. If the vehicle has over 100k on the odometer a transmission flush may create more problems than it corrects. If there are any external fluid leaks, have them addressed first, fluid leaking out can mean debris and moisture leaking in. If the fluid level and condition are good, I would then look at the shift detent cable that runs from the throttle linkage down to the transmission, it may be binding. I hope this helps you, and good luck.