1999 Cadillac Escalade Ticks only when cold starting

Where are you getting your oil changed at? Some oil filters are junk and do not have a ck valve in them to hold in the oil. In that brief moment this may cause your tick, otherwise it may be a lifter bleeding down, you can try heaver oil, like 10w 40 or 20w 50, or add some oil additives, like Stp oil treatment, or Lucas. If this doesn't help take the car to a certified mechanic.