I've become a geek about torquing fasteners. Typically I find I either grossly overtorque (valve covers, hub flange studs, oil filters, fill and drain plugs, intakes, etc.) or grossly undertorque (calipers, suspension, u bolts, etc.) The bad thing is on some components, and I think back to my stripped caliper bolt, sometimes the torque value is really high and guessing can lead to fasteners that yield, or stripped mating threads. Consistent overtorquing can also lead to failed mating threads in softer materials like cast iron. As an example I was watching George's video on t case rebuilds a few days ago and he zips things down with an air wrench or by hand everywhere. While with experience that can be just fine, and a lot of full time very experienced mechanics do it this way I just don't have the right touch I've found. Even with years of building things. When I worked in a transmission shop years ago the guy I worked with would do everything with an air impact. even the 10mm Head, 6mm thread bolts that hold valve bodies one... I don't ever think I could do that correctly. Also, a lot of times our stuff comes apart too often to risk stressing the threads.
On whether to use loctite or not, I have not used it much on caliper bolts. I like to go by factory recommendations. Same as I liek to do with gaskets... If they call for an added sealer I use it. if not it goes on dry. I've found that on everything except for british stuff and specific parts people have a lot of data on doing it this way has yielded good results. With British stuff if you don't use Hylomar, tons of silicone, or something else you are going to have leaks. And you'll appreciate the Hylomar when it comes apart the 1,000th time. You'll also strip all the coarse SAE threads if you tighten them enough or they'll come loose. That is kind of a joke but true. With stuff like Porsches there are all kinds of specific things I learned when I went to Porsche engine building school you are supposed to do that deviates from factory. it is well documented and based on years of data from previous builds. With Toyota, so far, for the most part, like factory recommends has been fine. Now do Iuse loctite on stuff I am worried about? Yeah probably. As long as I want it to come apart.. then I use blue. I'll use red if its a fastener that I can't get perfectly clean. If you use red on a perfectly clean fastener and they don't get heated (like a caliper bolt maybe) they usually don't come out very easily. I think that's why most people who use red get away with it.. it goes on bolts that get hot or aren't clean.
Now I'll eat my words when the caliper bolts I torqued to spec with no loctite on the 80 come loose lol.
