air dryer 1970 gmc 4905

[johnjem]

does a 1970 gmc 4905 come stock with a air dryer? after playing around with my bus<toys> i never recalled ever hearing my dryer release air my psi on my gage panel was reading well over 140 <my books are not with me at this time so i cant read them any info on this subject?

[TomC]

Like all else, the air dryer was optional.  In fact they still are.  If you don't here the air release when the compressor stops, then you don't have one.  Highly recommend you install one.  Most of the air system parts do not like water in the system.  Good Luck, TomC