Also check your clutch adjustment. It has to be EXACTLY correct, as per the manual, or you will have problems.
btw, If you are changing the oil every 3,000 miles then you are throwing money away. Scheduled maintenance is every 10,000 miles, and manufacturers are going to make services earlier rather than later because they don't want problems. If you don't believe the engineers then maybe change at 7,000 to be doubly cautious - or just change the filter every 5,000 miles. Modern full-synth oils are a very different animal from the old fossil oils.