Don't let tyre fitters tighen your wheel bolts

[Leslie]

Swapping over to my 21" summer wheels and was in the tyre fiiters getting 2 new rear winters on the rims and watched them uggga dugga the wheel bolts with an air gun and then use a torque wrench to check the tightness Not surprisingly them all clicked straight away , the front were fitted a few months ago and its about the only time I let then tighten the bolts due to covid distance rules, I usually do them myself with a wheelbrace and torque wrench in there . I did remove the locking ones myself as the airgun will knacker them and leave you stuck unable to remove them yesterday .

I tried to undo the fronts today and there was not shifting them with an extended wheelbrace so I pushed harder and the socket split most have been about 250-300nm It took a 600mm long breaker bar and an thick wall air impact socket to get them undone and a huge effort at that thought I was going to need a piece of pipe on them .
Lesson learned will not let it happen again , below the now binned socket

20210729_135915.jpg (153.47 KiB) Viewed 1457 times

[X5Sport]

Ouch!! I wonder if it's stretched the bolts at all? Where I go uses a proper torque wrench and only uses an impact drive to undo them. He owns a Porsche of his own so makes sure his team of two only ever do the wheel bolts the right way.

[Leslie]

That sounds like a proper enthusiast outfit
One that the socket slipped on is rounded a bit , I might do away with the locking wheel bolts as they are a pain and if it failed in one of the deep reach alloys you would never get it off again. The bolts are very tough Id be more worried it could split the alloy taper but I may need to buy a few spare bolts soon anyway.
Unfortunately I've been at another tyre place not that long ago and it seem the norm to ugga dugga then use torque wrench after , its what they have been shown I guess so a training issue, place I usually go to were fine with me doing up my own even if they thought it a tad strange
I guess it's more work for them and all they are worried about is being sued if one comes off so too tight ain't an issue.
At the side of the road I had zero chance of undoing those wheels. I thing a long breaker bar and a 17mm IMPACT socket, not an ordinary one as it will fail ! should be in everybody's toolkit and the preset 140nm bmw torque wrench someone said about on here is excellent to tighten them up again.
Anyway the 21's summer wheels are on at last , had to wait till the rear 20's were done first . 15k they lasted not too shabby when you put the correct pressure for normal tyres in them not the runflat pressure which is too low for a normal tyre ! The fronts were ruined in 5k with 32psi in them , outer edge buffed bald near 7mm on inside !

[sapphireblack]

Tyre fitters generally have the finess of a gorilla ime.

The windy gun then torque wrench approach is laughable at most tyre emporiums as who knows what the guns are set at. Bet the operator doesnt even know

Whenever a professional touches the wheels i always crack them undone again and re-tighten. And i now have a BMW pre-set wrench to accomodate that function too

[henrym3]

Surely if you have a pre set torque wrench, over time the torque and therefore the bolt tightness diminishes. Isn’t it normal practice to reset torque to 0 when finished the task.

[sapphireblack]

Surely if you have a pre set torque wrench, over time the torque and therefore the bolt tightness diminishes. Isn’t it normal practice to reset torque to 0 when finished the task.

BMW or Heyco would need to answer that. That said the BMW item is literally pre set and non adjustable.

[Leslie]

It meets bmw's approval but yes I see what you mean but it is only ever at 140nm when in use and clicking so maybe it's not an issue and it's not adjustable so nothing you can do..
Sappireblack you are right if you want it done right you do it yourself imo it's a training issue the fitters are only doing what they are shown/told

[StuBeeDoo]

Surely if you have a pre set torque wrench, over time the torque and therefore the bolt tightness diminishes. Isn’t it normal practice to reset torque to 0 when finished the task.

Yes, it is. Torque wrenches should be "relaxed" when not in use. Decent wrenches can be re-calibrated. Usually the instruction manual says how often to get the calibration should be checked/set. Got to be honest, my go-to wrench is probably nearly 20 years old and I've never had it checked, but I always relax the spring when I'm not using it.

[sapphireblack]

I imagine the BMW/Heyco wrench that several of us bought relies on a simple spring mechanism. As it only serves one purpose at 140Nm there is little or nothing to go wrong or that requires relaxing. I've not used it yet but i will check its accuracy when i do. That said if it breaks consistently and evenly then its better than excessive tightening on 1 or 2 bolts while others may be over or under. Most likely over and by an excessive amount.

[henrym3]

Leslie, your absolutely right, it’s all about training. Once watched a fitter use his torque wrench, after it clicked he done another 1/4 turn. When asked why. "Just to be sure"

[X5Sport]

[Leslie]

Know some people like that lol , righty tighty better too tight than too loose

[sapphireblack]

A one time brother in law, self employed mechanic, used to follow the FT rule, outside of the engine bay