Impact Torque wrench on tire nut

[jake jot]

A car service center used a hydraulic impact torque (is this the one used?) on the car tire nuts. See video. The car tire nut are rated at 88 ft lbs torque.

What is the estimated torque in the hydraulic impact torque? Could it be double or more? I know he should have used a torque wrench but didn't.

 

[BvU]

What is the estimated torque in the hydraulic impact torque? Could it be double or more?

Sounds like it's a lot less! So tighten by hand to stay alive.

Actually there is no estimate possible if nothing is measured.

$\$

 

[jake jot]

Sounds like it's a lot less! So tighten by hand to stay alive.

Actually there is no estimate possible if nothing is measured.

$\$

After that I bought a Torque Wrench and checked/tighten the nuts for the 88 ft.lb rating. But I was concerned if the impact torque has delivered more torques and could have overtighten the nuts. In the video, what is the estimated size (wattage and maximum torques) of the impact torque? is it hydraulic? Are the torques in an impact wrench adjustable?

 

[jack action]

The way to tighten "by feel" with a power tool is to quickly seat the nut and then give it a ¼ turn or so; you kind of "see it" tightening and get a feel for the angle you need with experience. It's a little bit like using a torque angle measurement.

You don't just put the tool on it and tighten it as much as the tool can give because, yes, you can overtighten it easily, maybe even breaking the stud.

 

[Lnewqban]

A car service center used a hydraulic impact torque (is this the one used?) on the car tire nuts. See video. The car tire nut are rated at 88 ft lbs torque.

What is the estimated torque in the hydraulic impact torque? Could it be double or more? I know he should have used a torque wrench but didn't.

That tool is fed by compressed air.
Please, see:
https://itstillruns.com/oil-impact-wrench-8153030.html

If your torque wrench was applied over an overtighten nut, it would still click at the specified torque.
The torque wrench should turn the nut some prior to reaching that point.

 

[onatirec]

Many shops use torque limiters with these pneumatic guns - but it's not clear that one is being used in that video...

 

[Mark44]

That tool is fed by compressed air.

Right, making it a pneumatic-powered tool rather than a hydraulic-powered impact wrench. Just for the record, I've never seen a hydraulic powered impact wrench.

IMO, it's OK to spin the nut on with an impact wrench, but then tighten it to 90 ft-lb or so using a torque wrench. Most tire shops that I've seen do exactly this.

 

[Lnewqban]

...
IMO, it's OK to spin the nut on with an impact wrench, but then tighten it to 90 ft-lb or so using a torque wrench. Most tire shops that I've seen do exactly this.

At least in Florida, most tire shops I know don’t bother using a torque wrench.
They also spin the nuts way too fast, to the point of damaging the threads by overheating them.

Last time my wife took our car to a tire shop, it took me half a day of sweating and fighting to lose those nuts, using an electric impact wrench and a 36 inches break bar.
After you apply the specified torque and use a cross pattern during installation of a tire, it is very easy to change a flat on the road using specific hand tools.

 

[Mark44]

At least in Florida, most tire shops I know don’t bother using a torque wrench.

That's not good, especially if they overtighten the lug nuts, and you need to change a flat while you're on the road.

Last time my wife took our car to a tire shop, it took me half a day of sweating and fighting to lose those nuts, using an electric impact wrench and a 36 inches break bar.

I had a car some years ago that developed a slow leak. The lug nuts were on so tight, I couldn't get them loose -- I didn't have an impact wrench at the time. I called a tire shop that sent a truck out with a compressor in its bed. He wasn't able to get the nuts loose, either. In the end, he inflated the tire enough that I could drive it the short distance to the tire shop, which had a beefier compressor than what was on the truck. At the shop, they still couldn't get the lug nuts loose, and ended up using a pneumatic chisel to cut them off.
I don't think it was the case that the lug nuts were on too tight. Instead, I believe there was some corrosion binding the nuts to the studs. When they finally got the lug nuts off, they recommended exchanging the studs for new ones, which I agreed to.

 

[jack action]

Just for the record, I've never seen a hydraulic powered impact wrench.

TADA!

https://www.spitznas.de/en/tools/impact-wrenches/hydraulic-impact-wrenches/615150010-en/

Oh! Before you ask, You can get a gas-powered one too!

​

 

[Mark44]

Oh! Before you ask, You can get a gas-powered one too!

Can I get a steam-powered impact wrench? That hydraulic one looks pretty beefy, with 3/4" drive.

 

[Averagesupernova]

One way I've had luck breaking free lugnuts is to use a cross wrench and while you have as much torque on that as you can muster have a helper hit the bell shaped socket that fits the nut with a hammer. a lot of times the impact will knock it loose. It should go without saying to be careful. Things can move in a hurry resulting in skinned knuckles, etc.

 

[berkeman]

One way I've had luck breaking free lugnuts is to use a cross wrench

What's a cross wrench? I'm off to Google Images...

 

[berkeman]

Oh, a combination lug wrench thing (I never knew the official name)...

https://www.grainger.com/product/46...1gRvS4yGDDfQcTQgSscaAj7XEALw_wcB&gclsrc=aw.ds

 

[Tom.G]

Around here, those shops that bother with a torque wrench at all, use an air impact wrench to install the lug nuts.

Then they look up the torque spec, set the torque wrench to match, and make sure the nuts don't move before reaching the spec.

Of course this makes a 'field repair' rather difficult! I use a combination wrench as shown in @berkeman's post above, with a wood block supporting the opposite end of the wrench. I then stand on and bounce on the wrench crossarm to break the lug nut loose.

From that point I give the wrench a good spin or two and the nut comes right off.

Addendum:
A few years ago we bought a newer car, one of those with the 'low profile' tires. I had always had the full size tires and cars before, and could drive over curbs and park by 'feeling' the curb with the tire. That does not work with low profile tires; the sidewalls are too weak. End result was my wife and I had lots of practice installing the spare.

I must have learned Something along the way, haven't needed a new tire in over a year!

Cheers,
Tom.

 

[Mark44]

Oh, a combination lug wrench thing (I never knew the official name)...

Years ago, 1969 to be exact, I had a VW bus that I had resurrected from a junkyard by installing a new engine that I put together, and half of the windshield. I was coming north on I-5 near Grant's Pass, OR, heading back to Ft. Lewis, WA when I had a flat on a rear tire. I had a 4-way lug wrench similar to the one shown in @berkeman's post. For the life of me, I could not break the lug nuts, and was merely deforming the lug wrench, twisting it.
Some time later, a trucker stopped to give assistance. With his beefier 4-way wrench, and possibly a length of pipe (it was a long time ago), I was able break the lug nuts loose and get my spare installed.

As with the car I mentioned in post #9, it probably was not the case that the lug nuts were overtightened, but rather that they were stuck due to corrosion.

 

[Mark44]

A few years ago we bought a newer car, one of those with the 'low profile' tires.

This one bit me in the butt a few months ago. Last year I bought an '02 Porsche 911 with low-profile tires. The rears were getting a bit thin in the tread, so I replaced them in April with a pair of Pirelli 265/35 R18 tires. In November I was driving somewhere when I discovered that one of them had gone flat, and in the process of slowing down from about 60 mph, the tire completely destroyed itself. Luckily I didn't have any problems getting the lug nuts loose alongside the highway I was on, to put on the spare, and the tire company replaced the tire at no charge.

I took the wheel with shredded tire to them, rather than drive on the spare 20 miles, and had them mount the new tire. I used my impact wrench to spin the lug nuts on loosely, then torqued them to 90 ft-lb.