Truck has 140,000 miles on it. When it's cold started it is usually quite for the first 30 seconds then developes a loud very noticeable tick. It ticks all the way till just about operating temp the it quites down. It will also cycle in and out while warming up, with the tick getting at its loudest then dropping back down to barley noticeable and working it's way back getting louder again. Any idea as to what the problem could be?

 

It could very well be a cam follower or some thing in the valve train....BUT...considering that it is intermittent in nature I would sooner suspect that you have a exhaust leak or cracked exhaust manifold. The Bolts on the exhaust manifolds are notorious for rusting and or breaking.

Is it more noticeable one side or the other? Is coming high or low from the engine compartment?

 

I don't personally think its exhaust related, but I've been wronged before lol. It sounds like it coming from the top end to me. I was originally thinking it was a lifter bleeding off, but what makes me think other wise is the fact that it doesn't instantly start ticking when I start it. It takes around 30 seconds to start doing it.

 

Might be good to get a mechanical oil pressure gauge hooked up and note the psi readings, on start up, when the noise starts & after the engine is up to full operating temp. After up to temp note the oil PSI on idle and 1500-2000 RPM.

To help pin point where the noise is coming from, maybe invest in a mechanics stethoscope.

 

next thing is oil level and when was the last time it was replaced. i have worked on several E series vans with the 5.4 with almost the same problem and the oil level was low and they had not changed the oil in awhile which some of those engines had well over 250k miles. first thing the shop wanted us to do was change the oil and add a oil supplement like lucas or hyper lube if that did not fix the problem then we had to do some digging into the engine to see what was causing the sounds

 

Last time my truck made a loud tick sound, spark plug blow out of it about an hour later.