[dshealey]

There are some experienced mechanics that have developed a good "feel" for torque over the years, but tests have shown that even the best mechanic tends to over tighten rather than under tighten.

I am an engineer who has worked on MANY types of industrial equipment, and all my vehicles for decades, and have 5 different torque wrenches, down to 1/4 drive Inch Pound.

I do not use them on everything by any means, but do use them on many things, such as wheel studs, and most engine/suspension/drive train items. I also use them on spark plugs that are in aluminum heads! Not so critical on cast iron heads, as I developed a pretty good feeling for that, but aluminum heads are MUCH easier to damage, so using a torque wrench is a very good idea (along with anti seize on the threads).

I refuse to let a tire shop use an impact wrench on my wheels when getting tires or rotation/balance jobs! Even if they use the "torque sticks" on them, many of the employees in shops do not know how to use them correctly, or use the wrong ones. I take my torque wrench with me, and ask them to just snug them up and I will torque them. I try to stay there and be sure some knuckle dragging tire jock does not get the word.

I have had TWO shops break wheel studs in the past.

Inconsistent torque on the wheel bolts can cause brake rotors to warp, or damage aluminum wheels so that they start developing microscopic cracks around the stud holes. Using a torque wrench set to the proper torque, and done in the proper two pass 'star' pattern can save you a lot of future grief, for just a couple minutes time. Of course there is the cost of the wrench up front, and good ones are not cheap. Even a relatively cheap "Harbor Freight" style is better than nothing because if not exactly the right torque is achieved at least they will all be CONSISTENT, almost as important as the torque value.