I see you have been useing a HM 4.7 CDS I just bought one a 1996 and am having problems with low heat ... only about 95 it should be about 180 to 200 right? here is some info...1996 Chev ... HM 4.7CDS .... water temp is only about 95 , I have some other possible related problems . (1) van heater blows out luke warm air, (2) temp gage on van looks like is only heating up to about 150 , The heater core seams to be in good working order so why would the heater/defroster blowing out only slightly worm air? I changed the therstat in the van but that did not help at all. I think the temp at the wand should be at least 180 or so. what do you all say? Thanks for any help you can give!