Incompetent Mechanics and Impact Wrenches

No one should ever use an impact gun to run nuts down, but if you're an incompetent ham fisted idiot, you should be shot for getting within 20 yards of an impact wrench.

Working on a Toyota, and every wheel had a lug nut cross threaded and rammed down with an impact wrench.

Pretty much a universal rant.

We used to service a fleet of GM 3500 vans (Advance Auto Parts) and the #1 repair on every one was always pulling the rear axle out of the vans to put in new wheel studs. We had a no impact policy on all of them and still replaced one every trip.

Once while rotating the tires on my parents Volvo, I bent the factory lug wrench in an attempt to remove one of the lug bolts after he had the car serviced at the Volvo dealer. He was in his 70's at the time and I'm glad he didn't get a flat when he was halfway to Florida.

Comon- they do it in NASCAR- should be good for the average mechanic...

On a VERY long trip to help my dad move from Fla. back to Texas, we had a wheel come off the enclosed trailer (double axle, luckily). We managed to find a dump truck shop that welded a stud back into the drum for us, put the well used spare on (the wheel with the good tire was shot at that point), and went on our way.

Later on the trip, we had a new tire put on the spare wheel, and I specifically told the mechanic to take it easy on the lugs, cause I didn't know how good the tack weld was on that one stud. Sure enough, he runs that nut down full blast with an impact and breaks the tack weld loose. I wanted to wrap the air hose around his neck.

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.

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.

Tire guy in the shop just will not listen sometimes.....after all they are the "professionals".

A friend bought some wheels from a Pick-N-Pull that came with "tuner" nuts. Silly design that used a 6 pointed star adapter that fit inside the lug nuts.

I recognised the danger and advised him to get some quality gorilla tuner nuts and still do not ever use an impact wrench. I even put the adapter in a plastic document tag holder with a warning "Do not use impact wrench, damage will occur"

Fast forward to the new set of tires from a reputable tire chain.... My friend, lets just call him trusting idiot, told the counter guy about the impact ban, showed him the note and walked across the parking lot for a Whopper.

Upon return, he sees his car up on the lift with no activity and he watches and wanders around because it was reported as not ready yet...45 minutes..slow day...he waits.

Then he sees a local parts store truck pull up, hand a tire guy a package which he opens, slips into his impact socket and installsseveral lugs with it in rapid fashion.

Trusting idiot fails to scream bloody murder at this point and the car is quickly off the rack and the counter guy is asking for money. When idiot notices the charge of $12.67 for misc parts, he wisely asks what it was and was told that the old adapter had stripped and they had to buy a new one. Idiot (now getting smarter) tells him that he warned about using an impact and doesn't think that he should pay for a part they damaged.

A staring, stammering standoff ensues and idiot calls me as I am in possession of the shiny happy person gene and only 4 blocks away.

Upon arrival I discover they had put the stripped adapter back in the bag and the new one was in the toolbox of tire guy and 3 of the lug nuts were split and stripped.

Counter guy was trying to cover his butt, tire guy was trying to cover his butt until I challenged them. "Remove 3 lugs of my choice with the adapter that was returned to us and we will pay for the tires ($545) and leave in peace."

3 hours later we had a new set of quality tuner nuts installed, $100 discount on tires, and I got to lecture, with accusatory and demeaning tones, the terror and cost of shoddy work, failure to follow valid instructions, theft and lying.

Once we were done I bought the crew pizza and let them know that now that I was convinced that they would never let this happen again, I could recommend them to my friends. They even worked up a list of discounts and deals for my fellow pizza deliver drivers. Good people that had just gotten sloppy.

Bruce

Last year I took my old ford truck in for a state inspection. I used to deal with this small mom and pop garage for that kind of stuff. So I show up about 1/2 hour before lunch...and no one is around except the grandson...we will call him "the kid", who is licensed to do inspections. So the kid says yea I can get you in...pulls the truck in and starts look stuff over. Then I hear the impact come out - I look out in the shop, but couldnt see anything as he was working on the opposite side of the truck from me. About 45 minutes pass and he comes in and tells me that I have a bad ball joint (which is odd considering the whole front end had been replaced about 2 years prior)...I just shrugged it off and went on to the big box auto parts store for some $13 ball joints. On the way I heard 3 loud "bams" from the back. It seems "the kid" had tried to take the rear wheel off with his big impact gun in the tightening direction and not only stripped 3 studs, but had broken them as well...I got it home relaced the studs and took it back...By this time Dad was there so I showed him what happened, ended up getting a free sticker. But I cant say that I would reccomend that shop anymore!

Let me provide some technical, engineer-ie type information to this discussion.

And impact gun is, at best, +/- 50% on torque. And that's if you actually have a "nominal" value that the impact gun will deliver. Most people have no clue. So you WILL end up with either under or overtorqued nuts/bolts. The only way I ever use an impact for tightening is on the lowest output force setting, and releasing the trigger just before the nut/bolt is run in all the way. Final tightening is ALWAYS done by hand, with some sort of torque wrench. I'm anal now, I torque my lug nuts with a torque wrench. A decent torque wrench will get you +/-25%, but at least you have an idea what the target is you're shooting for.

There are some torque-controlled impact-type guns and other automatic tightening tools, some of which have good accuracy control, but I venture to guess most casual mechanics and even many tire shops don't use these.

Would you use an impact gun to install the nuts on your big end caps? Then why use one on your tires? If you throw a rod, the worst that happens is you'll be stranded. If you lose a tire, well, you could end up dead.

I'm the only one in my high end dealership that uses torque sticks. All others play Asscar pit crew. And I ALWAYS start the lugs by hand to be sure they're threaded correctly. Never had a problem in 18 years in the business.

Torque sticks are pretty good. I worked at a valvojiff quick lube place in a former life, and tire rotations was a service we offered. One day we had a customer interject as we went to begin tightening his lugs with the torque sticks that he only wanted a torque wrench used to tighten his wheels. So we did as he asked, but after her left we pulled in my car, and I pulled all the lugs on one wheel, and re installed with torque sticks. We used a torque wrench to remove them to measure (approximately) what force was required to remove the retorqued nuts. All 5 were within several lbs of each other, and were all a few lbs less than the sticks "Max" capable torque. Id trust them over the little thumb knob on an impact gun any day.

Since buying a cheap N-T cordless impact, I rarely use my air impact on lug nuts. That said, it's only used for removal and intital installation, with final tightening with a torque wrench.

I almost NEVER take an entire car to a tire place. They always get loose wheels to swap tires on. Don't even give them a chance to be a gorilla. The only time I've negated this rule was with the truck (since it only has one set of wheels). Even then, I know the guy who was installing the tires, I was in the shop with him while he was doing the work and he's just as anal-retentive about torquing as I am.

We don't trust the torque sticks anymore at our Mechanic's Ministry. The air guns aren't always able to put down the torque though. Now air guns are allowed only for removing wheels and spinning down lug nuts, but never for the final tightening. That is done by torque wrench only.

Yea, I know the problem is common, but in this cars case, it was award winning. It was clear that it was the same ham fisted idiot who did all four wheels. He'd hang the rim on the top wheel stud, let it tilt, and then ram the nut on facing the wheel, at angle to the wheel stud. Every single wheel had exactly the same damage on one stud and nut.

Ian F wrote: I almost NEVER take an entire car to a tire place. They always get loose wheels to swap tires on. Don't even give them a chance to be a gorilla. The only time I've negated this rule was with the truck (since it only has one set of wheels).

I've pretty much taken this same approach. Even if I don't have other sets of wheels/ tires, I'll let the vehicle sit on jackstands as I cart the tires off to be swapped.

Just had to replace a wheel stud on my wife's van - same issue.

The problem with torque sticks is that they require fairly standard air pressure. If it dips they can become inaccurate. And, if the impact gun gets cranked up from where they were calibrated, you can get some over torquing. Not a lot, but it isn't good for the sticks. I've had two torque sticks shatter when another mechanic grabbed them from my box and cranked up his gun. I prefer to use the next lower torque stick and then torque wrench the final 20 pounds.

Old A-body Mopar guys know about impacts and lugs. Left hand threads on the left side of the car and ancient 7/16" threads just add to the mix.

That's why I have fairly new 1/2" right-hand threaded lugs on the Valiant now.

Double post - I also did brakes on my dads van with tires just installed. Every one was torqued over 140lbs. I told him should go back and demand new lugs and studs.

When the idiot in my previous post over torqued things we would always replace all the lugs and studs at no charge - if we found out about it.

People also forget that besides broken studs you can also cause rotors to warp.

My biggest disappointment with most car shows like Wheeler Dealers, he always guns on the nuts. Almost every bolt on a non classic car has a specified torque. Rarely do people look them up.

I have an IR gun at home. After getting my car back from my friend who is also my mechanic, I couldn't remove the wheel bolt with my impact, nor the biggest breaker bar I had. His shop had changed the wheel bearing in that corner. I called and I went to the shop for him to fix it. His somewhat new tech was the culprit. The time and effort to remove that bolt was substantial, all while I watch. My buddy was getting more red and more annoyed by the minute. Finally fixed, he sent me on my way. I don't envy the lecture the new guy received when I left. I don't ever remember seeing that tech at his shop ever again.

I usually hand thread the nuts, use the impact to snug them up, and torque wrench for the final tightening. Oddly enough I don't trust that my impace will get them tight enough....ya I know, I'm wierd, but my first impact gun before this IR was real cheesey piece of garbage.

>>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.

slantvaliant wrote: Old A-body Mopar guys know about impacts and lugs. Left hand threads on the left side of the car and ancient 7/16" threads just add to the mix. That's why I have fairly new 1/2" right-hand threaded lugs on the Valiant now.

All the old Mopars had the LH threads on the left side of the car. I had a tire shop bust studs on my '67 Imperial once because of this. The studs are even stamped "LH" on them.

I'm amazed at how little one has to know to be a mechanic these days. ducks

This was a sore point with my Jeep dealer. Any time I took it there and a wheel was removed/reinstalled, the nuts were tightened 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.