Wanted to share my results after installing a Fluidampr viscous harmonic damper part # 830111 on my 2008 LMM Duramax. Install is very straight forward and took about 1 and 1/2 hours to complete.
Fan clutch removal kit
Body clip tool or pick + small flat screwdriver
Lisle Duramax flywheel locking tool(comes with damper bolt socket)
Large steel 4ft cheater bar! Eat your wheaties and be at least 200lbs or you will have trouble.
3/4 breaker bar (1/2 will snap).
13mm short socket for 3 fan guard bolts
Bar stock steel to lock water pump pulley if LMM.
Surpentine removal kit or 1/2 breaker bar.
**** Make sure you trim the lower fan guard as it will rub on the front of the damper. This needs to be added to the instructions!
This essentially goes the same as a water pump Tear down with exception of pump removal (unless you are ultra anal).Install flywheel locking tool. Remove old damper and clean crank snout with Brakleen. You will re use the factory damper bolt. Lightly coat the snout with anti seize. Guide the fluidampr on making sure to align the keyway. Push until the damper seats all the way back on shoulder of crank(you will hear a thud when it is seated. Install bolt and torque to 74 ft lbs. Now mark the bolt so that you know when it has been turned 105 degrees as per Fluidampr's instructions. Now install belt, fan assembly and button up the top shroud. I always disconnect the battery's whenever I do any engine bay work. VERY IMPORTANT!!!!! REMOVE LISLE FLYWHEEL TOOL. If you try to start prior you will cause damage to flywheel and starter. Double check everything and start to check operation. ** please note this is only for reference. Always double check manufacturers written directions and consult a professional if you are not a proficient mechanic.
All I can say is WOW! My LMM sounds like a LML. The engine vibrations have been cut in half and power seems up a little(might be psychological). But vibration and sound are dramatic. Even the transmission seems to shift a bit more smoothly. Overall I am very impressed. Keep in mind that my truck is low mile and mostly stock. For power add on's these shine even more. This technology has been used in big rig over the road diesels for years, and I can see why! Any questions please feel free to ask.