I've yet to see a youtube video that isn't by a real mechanic that has good info in it.
If you under or over torque things you open yourself up to a host of problems. Over torque and you can damage the fastener, it may not fail immediately but it will probably fail. Under torque is the same, gaskets may not seal right or you may have enough movement for vibrations to work things loose, if the fastener goes into the oil or water channels it may leak and work itself loose, or the vibrations can damage the fastener.
Torque spec is of the utmost importance on some fasteners where it sets the preload on a bearing. Wheel hubs, diff bearings, etc are common failures when not torqued properly.
This is from the lugs being overtightened by the PO, they were installed with an impact gun instead of a torque wrench, the lugs disintegrated. It could have been much worse.
1996 ZJ Green Laredo V8, 2.5" OME and Bilsteins, 33's, Holes drilled in the roof.
1998 ZJ Platinum Limited 5.9, Backyard parts fodder
1987 Mercedes 300D Turbo, the diesel daily, 30mpg in style
Originally Posted by Texas ZJ1
I heard someone yell "mall crawler" from the back porch. I'll go see who said that. Be right back.