Thank you all so much for the replies to this. As it turns out I needed to travel for business this week so I am in Chicago and Houston but my bike is back in Florida. My intent is to try the tension adjustment suggested (shifting from gear 11 to gear 6 is brilliant) and if that doesn’t correct the issue I will swap the gear oil. The price for the Shimano gear oil and drain kit is outrageous! The Royal Purple option is a good one.