Ford Repair: Ticking, oil filler cap, manifold gaskets

Question
I know its not a Ford but please respond!!!Hi i have a 92 Chevy 1500 4x4 5.0 V8 168000 miles, i havent made any modifications to the motor or exhaust, and the only thing i have done so far to try to fix the problem is I changed the oil and filter and ran seafoam in the oil.Anywway i have a problem with the motor and/or the exhaust ticking. It ticks at idle and as the rpms rise the tick becomes faster until the noise grounds out. The motor has normal oil pressure, its not burning oil, and theres no loss of power. I got under the truck to try to pinpoint the location of the noise but had no luck. I noticed a small leak coming from one of the exhaust doughnuts but Im not sure if that would cause this noise. Can u please give me some suggestions or any kind of help.

Answer
have you ever noticed a milky color on your oil filler cap indicating water in the oil-these were bad about intake manifold gaskets leaking coolant-either inside engine or outside if it leaks inside water will run down into lifters on the corners and they will start to tick and can sieze up at times and start skipping-if you have an exhaust leak you can try pouring a small amount of trans fluid down throttle body while truck is running and look for smoke out exhaust manifolds and pipe don't pour to much at a time or you can cause engine damage. good luck. you can also try adding marvel mystery oil to oil and running it some in case it is a lifter noise.