I think what happen is I got it hot when I pull my grain trailer home in July. Because I remember the water temp was very hot that day. And I had a SPA gauge that never seem to read right. SO after that I put different gauges in and the EGT reads a lot higher than SPA gauge did. But after that day the motor always seem to be a little louder then before. And it had about 21,000 on then and now it has 30,000.