June of last summer the car started to slip slightly when pulling out from a dead stop. Did this three or four times over the course of a couple days then didn't do it again for several weeks. The car will slip slightly then engage suddenly. After that it shifts perfectly, drives smoothly, etc. It will do this for a day or two then not do it again for a month or two then it will repeat this cycle. Any idea what is wrong anyone?

Has the vehicle ever been scanned for powertrain codes?

Has the feeling of a P1811....