Hi Guys,
While my truck's not plagued too badly with the tick, immediately after an oil change, it is audible and gradually fades to inaudibility within 1,000mi or so.
I started looking for the source of the tick with my wife's stethoscope and realized the sound was emanating from the oil filter mount. Being the destructive dufus that I am, I removed the housing and tore it apart. What I found puzzled me. Inside, I found a very complex mechanism that appeard to be a hydraulically driven trip-hammer with a very complex device attached to it.
About this time, the wife caught me with her stethoscope. Angry doesn't quite cover it... but the making up's gonna get good. 
Not being able to figure out the device, I tried another approach. I reassembled it and fired up the truck and recorded 1 hr of the ticking into the laptop. I converted it to a .wav file and used spectrum analyzers and waveform analysis to try to discover what it was, no joy.
I then used advanced cryptoanalysis software available from our friends (www.cia.gov) to analyze it. This is the same software (brute force method) they use to crack PGP encoded email routinely and is used on distributed platforms similar to the SETI@home project.
Here is the shocking part. The tapping is not random. It is actually Morse code, formatted in BCD and encrypted in very weak 128 bit encryption, exactly like what is used in your browser, compliments of Microsoft.
Here is the decoded text:
"Congradulations!(sic) You have successfully uncovered the secret hidden within the most powerful, quietest light truck diesel engine on the planet. There are similar messages hidden in the Ford "cackle" and Dodge clatter, but we're confident those will never be discovered, for obvious reasons. This message brought to you by... (long list of mechanical and electrical engineer's names). Now get a life!"
In the software world, these are called "EASTER EGGS".
Happy Easter, everyone!
Hopping away, Steve
[ 03-31-2002: Message edited by: SoCalDMAX ]</p>
\'02 2500HD 2WD LS, grey, CC, SB, D/A, locking diff., alloys, trailer and towing pkg. Delivered 11/09/01<br />So far:<br />Juice ver 3.61c, Max Power Plug, PS2000 propane, Gibson Performance dual exhaust, 255/85-16 Dunlop Rover A/Ts<br />Pillar mounted SPA Boost/EGT/oil press./oil, tranny, diff. temp gauges, Valentine One<br />Aiwa CD/MP3 head, 4- Pioneer TS-C1653 6.5\" component spkrs, 2-10\" Tsunami subs, 1200W of Visonik amps<br />Jordan 2020 Ultima Brake Controller, Lucerix mirrors, Line-X, Bed X-tender, DeeZee running boards<br />Peragon folding bed cover, Rancho RS9000 shocks<br />PIAA headlights, Power tailgate lock, Invinca-shield, Husky flaps and tinted windows <br />Mag-Hytech diff. cover, Allison deep sump, Transynd, Amsoil air filter and gear lube, Fumoto valve<p>Up next:<br />high idle, Spare fuel tank?<br /><a href=\"http://www.pbase.com/sfrakes/2002_silverado\" target=\"_blank\">Truck Pictures</a>
