Checking wheel torque?

Loosen and retorque to 90lbs. Dont use the torque wrench to loosen it to avoid damage

macrossr wrote: ↑ Loosen and retorque to 90lbs. Dont use the torque wrench to loosen it to avoid damage

Thanks
I don't understand the damage part though unless I exceed the wrench specs. Torque wrenches work on noth L & R hand threads. If I take my wrench that is good to 150 and set it to 100 then try to loosen the bolt. If the bolt loosens without clicking wouldn't that mean the bolt was originally torqed to < 100? Conversely if the wrench clicks without moving the bolt was torqued to > 100?

If not exceeding the max torque for loosen, its no more wear compare to tighten, however its still more unnecessary wear as you can use something cheaper like breaker bar to loosen nuts which do not require calibration and save the torque wrench to tighten only.

I only use the torque wrench for that last 5% torquing. Everything else breakerbar or a ryobi electric torque wrench.

How do you know? You do it yourself.

Short of re-doing the work entirely, just check that it's up to spec and that's the best you can do. You have to trust that whoever put the wheels didn't crank them down with an impact wrench way over the spec.

And a torque wrench is a precision measuring instrument. If you're not doing that, you should be using a different tool.

derass wrote: ↑ How do you know? You do it yourself.

Short of re-doing the work entirely, just check that it's up to spec and that's the best you can do. You have to trust that whoever put the wheels didn't crank them down with an impact wrench way over the spec.

And a torque wrench is a precision measuring instrument. If you're not doing that, you should be using a different tool.

@derass Doing it myself was not an option.
Bought new tires @ CDN Tire. They would not mount and balance unless they also installed on the vehicle. (A really stupid policy for a number of reasons)
Given the numerous horror stories of CT auto service, I wanted to see how bad they actually were.

I've done a few cursory searches on the web and found out there is something called "breakaway" torque. From what I was able to gather the amount of torque required to loosen a bolt will be a little more than the torque initially applied to it. Nobody has really said how much the difference is.

Given that the acceptable standards for a torque wrench are +/- 4% and a little more torque is required to "breakaway" I'm thinking at a deviation of 10 ft-lbs would be acceptable. (On edit, I found a video that says a 10-15% is normal)


Anything more & it should indicate the bolts were over torqued. Anything less than spec, would indicate they were under torqued or had loosened.

One day this week, when the wife is not using the car for work I'll try measuring the break away torque. After 20 bolts, I should have a good idea. Then maybe a week later, I can check a few again knowing what they were actually torqued to in the first place. With this pandemic, I've got some time on my hands.

Regardless who did it, grab a torque wrench and set to 90 or 95. You should be able to feel the lug nut/bolt move while you hear the click. If all lug nut/bolt move tiny bit, then you did a good job retorquing. If they don't move, the sob at ct overtorqued.

peteryorkuca wrote: ↑ Regardless who did it, grab a torque wrench and set to 90 or 95. You should be able to feel the lug nut/bolt move while you hear the click. If all lug nut/bolt move tiny bit, then you did a good job retorquing. If they don't move, the sob at ct overtorqued.

Thank you @peteryorkuca !
Another fine example of the simple obvious answer being overlooked by my overthinking.

My cumpare said over-torquing is better than a loose wheel falling off during a drive on the highway.

@ROYinTO Yes, you can check the breakaway torque, but that's what I meant by "redoing all of the work".

If you start checking the breakaway torque, some of the wheel nuts are going to loosen completely.

Wheel retention is all about even, appropriate clamping force. That's why wheel nuts are loosened and tightened in a star pattern with the tire off of the ground.

If you loosen one wheel nut with the tire on the ground, you have suddenly introduced uneven clamping. If one wheel nut is loosened, the rest of them should be loosened as well, and then the wheel reinstalled.

McLaren__F1 wrote: ↑ My cumpare said over-torquing is better than a loose wheel falling off during a drive on the highway.

That's likely what got me into all of this. Last fall when the Mrs brought her car in for the seasonal tire swap they broke the heads off 3 Benz wheel bolts leaving the base still holding the alloy wheels on. Had to bring it elsewhere to get them drilled out. Add in the cost of new wheel bolts & the total was >$500.
So yeah, I'm a little paranoid about a grease monkey over torquing wheel bolts.

Thanks @derass looks like I'll be redoing it all for piece of mind.

Did a random check today on 5 bolts. 1 loosened at the right torque, the other 4 loosened at 10 over without clicking. Retorqued them all with only 2 of the remaining budging a bit.
From that I'm thinking CT actually torqued them properly. I was worried that they went overboard with the impact gun.

peteryorkuca wrote: ↑Regardless who did it, grab a torque wrench and set to 90 or 95. You should be able to feel the lug nut/bolt move while you hear the click. If all lug nut/bolt move tiny bit, then you did a good job retorquing. If they don't move, the sob at ct overtorqued.

ROYinTO wrote: ↑ Thank you @peteryorkuca !
Another fine example of the simple obvious answer being overlooked by my overthinking.

If my car says 90 and if I set it to say 90… I wouldn't hear any click or movement with the wrench telling me the person torqued it right?

TorontoEh wrote: ↑ If my car says 90 and if I set it to say 90… I wouldn't hear any click or movement with the wrench telling me the person torqued it right?

Everytime you torque a nut/bolt, you want to feel it move just a bit when it clicks. If it don't move when it clicks, it's overtorqued.

I usually do 2-3 clicks per nut/bolt in star pattern.

ROYinTO wrote: ↑ That's likely what got me into all of this. Last fall when the Mrs brought her car in for the seasonal tire swap they broke the heads off 3 Benz wheel bolts leaving the base still holding the alloy wheels on. Had to bring it elsewhere to get them drilled out. Add in the cost of new wheel bolts & the total was >$500.
So yeah, I'm a little paranoid about a grease monkey over torquing wheel bolts.

And I though lug bolts were better than lug nuts

mr_raider wrote: ↑ And I though lug bolts were better than lug nuts

The bolts were a funky design.
Thread > 1/2 ball > shaft > bolt head.
They broke all 3 at the shaft leaving the 1/2 ball deep in the wheel.
Design was later changed.

https://sites.google.com/site/2001merce ... -bolts.jpg

It's a good idea to doublecheck somebody's work. I trust them, but want to be sure for our safety. I always assume the tire guys over-tighten and over inflate the wheels/tires. I set my torque wrench to the specified torque, apply steady pressure. The lug bolt/nut should move slightly after the wrench clicks. If it doesn't budge at all, then it's way over tightened. Crack them loose, then torque them down again. Also double check tire pressure.

ROYinTO wrote: ↑ Say the specs are 90 ft/lbs & somebody else installed the wheels.
I understand that by going and checking tightness with a torque wrench set to 90 ft/lbs you will know if they were under torqued or had loosened.

So how do you check to see if they were over torqued?
Try loosening at 90 ft/lbs? 95? or something higher?

Or do you just loosen and retorque without checking?
How are you people doing it?

Get an electronic torque wrench and check.