Incompetent Mechanics and Impact Wrenches

iceracer wrote: This was a sore point with my Jeep dealer. Any time I took it there and a wheel was removed/reinstaled, the nuts were on stalled with the so called torque sticks. When i tried to loosen them with a 18" bar I couldn't get them loose. I took it back and made them loosen then and tighten them with a torque wrench. After this happened the second time the service manager always put a note on the repair order."torque wrench only" Then I had a self quoted " master technician" tell me that a 3/4" socket was wrong , that I should use a 19mm. Then I "politely" told him that the lugs and nuts were SAE not metric. Has anybody seriously looked at these so called "torque sticks". I fail to understand how they can possibly work.

They have a precision machined section of the shaft that twists at a given torque. Once it starts to twist, additional torque just twists the shaft rather than tighten the nut.

Plus its a tempered steel to act as a spring - on the pass when the impact pawl opens and the torque on the gun stalls, the sprung steel flexes back = no more torques get put on to them wheel holder-onners. They do indeed work.

The concept behind a tourque stick is basically the same as a torsion bar; it will only twist so far, and no more.

Per Schroeder wrote: >>I usually hand thread the nuts, use the impact to snug >>them up, and torque wrench for the final tightening. Knock on wood, but years of autocrossing, tire testing and car work and this has been successful for me.

pretty much same here

my 3/8 IR ti impact at its lowest setting is pretty consistently at 95psi torquing to around 60-70 ft/lbs so long as you dont hang on the trigger. tight enough to set the car down safely, loose enough to get a proper torque wrench for final tightening.

With the torque sticks are supposed to work, then why were my wheel nuts so grossely overtightened, not once but twice. Even a torsion bar can be twisted excessively. I guess it still takes a competent "master tech" to use them. I looked a set and they don't look very precision machined to me. More like 3/8" extensions. I guess some one will have to prove it to me befor I will believe.

they make some pretty beefy sticks...its possible the hooligan grabbed the biggest one he could get his gorilla mittens on and then set his gun to ludicrous speed before having at your wheels. I am not 100% certain how many brands of sticks there are out therm but I could also see a set of HF sticks being made from cheapo fencepost steel vs a high quality cocktail that takes heat treating better. Without the springy-ness through heat treating, then youre right, they are little more than fancy extensions.

But sometimes you'll find competence in surprising places. When I bought my truck in western PA, I had a blow out on the way home. This being a Sunday, a Walmart was the only place open and by a small miracle, had the tires I needed in stock. Being somewhat fearful of mechanics, you can imagine my surprise when after installing the front wheels back on the truck, the service manager grabbed a torque wrench and torqued all 16 nuts on both wheels. The truck moved when she did it (150 ft lbs).

While I have no direct proof, I believe Wally World must have some type of policy that the manager will final torque all lug nuts with a torque wrench. I could ask the next time I get a tire done, but I've seen it many times at different Wally Worlds.

Personally, I start the nuts/bolts by hand, run them down with my impact set at the lowest setting (or with the air pressure down to ~50 PSI if my wrench doesn't have a setting), then lower it down so the wheel won't spin (depending on the vehicle/axle) and torque to spec with a torque wrench.

Walmart and Sam's Club policy is tech installs and torques lug nuts. Second tech or manager then resets the torque wrench and checks all nuts. Every nut is checked twice by two people. There is also a spec sheet posted listing all cars and torque for lug nuts. There is also a big nasty post on the wall about what happens if the techs fail to follow procedure. They don't do it because they care about you or your car. They do it because Walmart doesn't want to get sued again.

Toyman01 wrote: They don't do it because they care about you or your car. They do it because Walmart doesn't want to get sued again.

Oh, I don't doubt that... but if that's what it takes...

That said, I still don't plan to buy tires at Walmart again any time soon.

Toyman01 wrote: They don't do it because they care about you or your car. They do it because Walmart doesn't want to get sued again.

Good enough for me!

zomby woof wrote:

foxtrapper wrote: No one should ever use an impact gun to run nuts down

Nonsense. I do it all the time, and have never ruined a thread.

I get the intent of the thread, but yeah, I do too. Start them by hand, impact them up tight then final torque with a torque wrench. Little dab of anti-sieze every now and then. I'm one of those autocrossers who swaps wheels at the event. So I change them a lot. Never had a problem doing it this way.

It's not a matter of not doing it, it's a matter of not doing it wrong.

unevolved wrote:

zomby woof wrote:

foxtrapper wrote: No one should ever use an impact gun to run nuts down

Nonsense. I do it all the time, and have never ruined a thread.

Wrd. Like most things, it's OK in moderation. I've used one many a time, but only after I've hand-threaded the nuts, and I have the impact turned all the way down. I measured it once with an impact, I think it was about 55-60 lb/ft worth. It's a huge timesaver on cars with extended studs and deep lug mounting faces.

Me as well. I just learned the hrad way not to go town with the impact if I ever wanted to remove the lugs sans impact.

iceracer wrote: Has anybody seriously looked at these so called "torque sticks". I fail to understand how they can possibly work.

Your experience with them matches mine and most other folks I know. Torque sticks are for moron shops only. They don't work well and are generally forbidden by sanctioning bodies like the FAA and such. Don't know of any reputable shop that uses them.

They are an item that sounds great in theory, but that fails in actual application.

Honestly...

I think this is usually a rant where somebody who thinks they know how to do something they dont do for a living pays somebody else to do it anyway and then gets annoyed when the other person doesnt do it the way they think it should be done.

I can guarantee that in the forums specific to people working in auto repair that there are threads of mechanics complaining about how people who think they know how to do everything right still pass the buck to mechanics and then bitch about how they would have done it different.

You have no idea just how huge the percentage is of how often things go RIGHT using the methods you are complaining about. I use my 1/2 impact on EVERYTHING. Ive stripped out TINY fasteners once in a blue moon. Then i helicoil them and get back to work. The time i save is worth the occasional hiccup. If you dont like that and would do it differently, then please DO do it differently and stop bitching.

If you want something done 'the way you would do it yourself' (~right?), do it yourself. A much older and truer line than 'dont use impacts in ways i dont like.'

In reply to Vigo:

Vigo- the OP did say that all the lugs were cross threaded. That's just a "how it should be done" issue- that's gross incompetence- the prevention of such incompetence is the "how it should be done".

There's a big difference in overtightening or stretching from impact gun sent on kill and not stun vs. using a gun to cross thread, and just running them down.

Or going with your 3rd paragraph, where in mechanics school, is it taught that it's ok to start threading someting with a impact gun and just keep going no matter what?

What YOU do is very, very different than what happened to fox.

apparently I am a moron because Ive used (successfully) and understand the way torque sticks work. Ive already gone and gotten my stake, here is the rope and the gasoline, but youre on your own to find some matches. Now wheres my uncle daddy, I need my banjo...

Toyman01 wrote: Walmart and Sam's Club policy is tech installs and torques lug nuts. Second tech or manager then resets the torque wrench and checks all nuts. Every nut is checked twice by two people. There is also a spec sheet posted listing all cars and torque for lug nuts. There is also a big nasty post on the wall about what happens if the techs fail to follow procedure. They don't do it because they care about you or your car. They do it because Walmart doesn't want to get sued again.

Since the advent of the torque stick (yes they do work!) and the cheap clicker torque wrench I have a zero tolerance policy for overtightened lug nuts or bolts in a shop. There is simply no excuse.

I have had techs tell me they hammer on a lug nut 'because they don't want them coming loose'. I point out the raised 'lock ring' on steel wheels and the steel cone inserts on alloy wheels, then remind them if it comes back busted they fix it for free. I don't give a damn if they decide to quit, I'll help push the toolbox out. As I said, there is simply no excuse.

Here in the Garage Majal, I run them down with my impact on the lowest setting (which is around 50 foot pounds), then retorque by hand. Most wheels are around 85 foot pounds, there are some (old Isuzus, for instance) which require 65 foot pounds.

My (electric) impact wrench has a 2-way toggle switch for either forward/tighten or reverse/loosen. In almost ten years of working on my own cars, I've never hit the 'tighten' side of the button. A clicker torque wrench is a way better tool for that job, and nearly as quick.

slefain wrote:

Exactly what I was thinking.

Vigo wrote: The time i save is worth the occasional hiccup. If you dont like that and would do it differently, then please DO do it differently and stop bitching.

Nah, the fact that you do sloppy work and usually get away with it doesn't make it right, and doesn't preclude someone from observing that it's a poor way to do a job.

No doubt, I can slam the studs home faster on the jet engines were I to use an impact wrench. Faster still if I ignore torque sequencing. And most of the time, that engine would run when I was done. That wouldn't make it right, so I don't do it.

You may not care if a customers wheel wobbles when it leaves your shop, or if their brakes now pulse because you bent their rotor. F-em. You got the job done quick and made money. Fine. Shops like yours, I avoid. And I recommend to anyone I know to avoid work done by guys like you who believe they are wonderful with an impact gun and don't mind the damage they do to a customers car.

And I avoid the shops with high brow shiny happy techs who are the best wrench they ever met. Im sure any idiot can dork up studs in any fashion they want. Any tool, if improperly used, can cause damage. That being said, if used properly, a tool can perform many functions very well. Unless you know for certain that I personally effed up someones vehicle, dont tell me how low my intelligence is because I used a similar method to some mouth breather who doesnt care. You show me a mechanic of any skill level or education who claims they NEVER used a pair of channel locking pliers when a box wrench or socket and ratchet shouldve been used, and I will show you a damned dirty liar. Looking down your nose at someone doesnt make you better than them, it just makes you an ass.

Jensenman wrote: Most wheels are around 85 foot pounds, there are some (old Isuzus, for instance) which require 65 foot pounds.

44 lb/ft for Geo Metro

76 for the AW11 MR2, and you WILL warp the front rotors if you overtighten!

I've busted one or two lug nuts myself doing it the wrong way. Now I start them by hand, spin them down the stud with the IR, and torque by hand. And really, I just use the IR to spin the lug nuts faster than my hand will, not to actually tighten them onto the wheel. Or, if my hose doesn't reach (I don't have a cordless IR), I just do the whole thing by hand.