Ford Repair: 1999 expedition eddie baur, marvel mystery oil, change oil

Question
I am noticing a light but easily heard ticking from the engine, mostly when first started

Answer
which engine ohc or ohv-is your oil clean could be lifter noise-or exhaust could leak worse cold if manifold is cracked. if you think it is lifter and engine is running good put in 1/2 pint of marvel mystery oil and run it some then change oil and add other 1/2. good luck