My last oil change was in April, and this was put in: Filter: Bosch Distance+ D3330; Oil: 1 quart of Supertech 20W-50 SN, four quarts of Napa 10W-40 SL grade fleet oil I got on a sale in 2011, and 1 pint of Marvel Mystery Oil. I want to run the filter 15,000 miles and have now run 4020 on it, averaging a little over 40 miles per day. The filter will do it; I will leave the filter on at the next oil change which will be at 7500 miles. Do you guys think this oil change interval is OK for this 1996 Avalon? I just want to do scheduled maintenance all at the same time, such as a timing belt job, drain & refill of the tranny and cooling system, wheel alignment, etc. I am thinking of running 5W-30 Toyota dino in it for next winter but have not decided yet. That change will come around November 1st. Thanks.