<strong>Yahoo Message Number: 18133</strong>Hi all,<br/><br/>We have a 1993 Affinity with a 3176 Cat, which we have owned for the past 8 years. At a rally the other week I was told the Air Dryer on the engine needs to be changed or serviced every year. <br/>Although I have had several "full services" done over the years most of the time I just have an oil and lube at truck stops, so I really don't...