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took my car in for a 'dealer' service the other day. When I drove the car noted what I can only describe as a metal on metal type of sound from the left rear. Rather than go back to the dealer thought would drive it home first investigate myself. I went to take take the wheels of, but even using a torque wrench struggled to get the wheel nuts off. Forget manufacturers torque settings these things had been wrenched on. I managed to get them off and retightened the wheel nuts and the metallic sound has reduced by about 80% but is still there.

Outside of stripping the threads (which I think have been impacted somewhat as the wheel nuts did not turn evenly if that make sense), what are the implications of tightening the wheel nuts to tight on an MX5? Can yo do any damage at all to any other parts?

*too

It often results in a busted stud.

I would have taken it straight back to the dealer as soon as it made the grinding sound.

Use your torque wrench to "read" the torque of some of the other wheel nuts to compare how over tightened they were and go back for a please explain.

Using a torque wrench to undo over-tight nuts & bolts is a good way to ruin a torque wrench.

nbse2 wrote:Outside of stripping the threads (which I think have been impacted somewhat as the wheel nuts did not turn evenly if that make sense), ...

I guess you mean "cross-threading" not stripping. If you think that's what's happened then use a tap&dye kit to clean the thread.
I've never heard of overly-tight nuts making grinding sounds, it must come from somewhere else.

You didn't mention what kind of 'dealer' service was performed.

This why when anything is done involving the wheels on my car I take a torque wrench and ask that they only run them up and I will do the final torque.

Steampunk wrote:Using a torque wrench to undo over-tight nuts & bolts is a good way to ruin a torque wrench.
:

+1 - use a torque wrench for tightening to specs only. Use an impact wrench to loosen over-tightened bolts.

Black_Penguin wrote:This why when anything is done involving the wheels on my car I take a torque wrench and ask that they only run them up and I will do the final torque.

I have 6UL wheels and lug nuts and 949racing recommends "Torque lugs to 70~80 ft-lbs ( 94Nm~108Nm)". When I got my tyres fitted at Beaurepairs I explicitly asked them to torque them to 94Nm only, it was written on the worksheet - they'd be easy to loosen then. When I picked up the car I took along my torque wrench too. I used my tyre iron to loosen the nuts first and then torqued them up to 100Nm. EVERY wheel nut was hard to loosen up so I know that they just tightened the "bejeezus" out of them. I let them know I wasn't happy, I bet they've never had a customer check every wheel nut before, but when I got tyres fitted to my track 6UL, they did follow my instructions.

Tyre pressure is still an issue though, they always put too much air in.

the scrapping sounds is either a bent dust shield or the pad dragging on the rotor after a handbrake adjustment.

everytime i go the the tyre shop, the rattle gun those nuts on real tight. steel nuts, not a problem, alloy nut, well they already only have a 12-18 month lifespan, so it will shorten their life even more.

project.r.racing wrote:the scrapping sounds is either a bent dust shield or the pad dragging on the rotor after a handbrake adjustment.

everytime i go the the tyre shop, the rattle gun those nuts on real tight. steel nuts, not a problem, alloy nut, well they already only have a 12-18 month lifespan, so it will shorten their life even more.

Yep, I thought it might be the result of the pad dragging on the disc (or rotor?) resulting from the handbrake adjustment but why would it be then that that the loosing the wheel nuts reduced the amount of the scraping sound?

Also, with the wheel nuts, are the NB wheel nuts alloy and if so are these ment to be replaced periodically?

PS, it was just an "interim service" at 64000km.

Mechanics at fast food workshops don't get paid nearly enough to go tightening nuts to customer specs.

vrmmmpshhh wrote:Mechanics at fast food workshops don't get paid nearly enough to go tightening nuts to customer specs.

Yep, convenient, just up the road from were I live, but sadly you've mirroed my belated realisation on these operations. (Slightly off topic but not the intent of the thread)

However, while this may be the cold card reality of a dealer or "fast food" workshop, there remains no exuse for not doing it right. The sales/service paradigm is something that should be not be overlooked. Poor service will ultimately lead to brand disatisfaction and customers simply turning to another brand. Round and round it goes!

Lokiel wrote:

Steampunk wrote:Using a torque wrench to undo over-tight nuts & bolts is a good way to ruin a torque wrench.
:

+1 - use a torque wrench for tightening to specs only. Use an impact wrench to loosen over-tightened bolts.

Black_Penguin wrote:This why when anything is done involving the wheels on my car I take a torque wrench and ask that they only run them up and I will do the final torque.

I have 6UL wheels and lug nuts and 949racing recommends "Torque lugs to 70~80 ft-lbs ( 94Nm~108Nm)". When I got my tyres fitted at Beaurepairs I explicitly asked them to torque them to 94Nm only, it was written on the worksheet - they'd be easy to loosen then. When I picked up the car I took along my torque wrench too. I used my tyre iron to loosen the nuts first and then torqued them up to 100Nm. EVERY wheel nut was hard to loosen up so I know that they just tightened the "bejeezus" out of them. I let them know I wasn't happy, I bet they've never had a customer check every wheel nut before, but when I got tyres fitted to my track 6UL, they did follow my instructions.

Tyre pressure is still an issue though, they always put too much air in.

I was advised that the wheel nuts were torqued at 160Nm which is a fraction more than the RX8. Ive reduced it myself to 100Nm.

Imagine trying to change a flat with the small wheel brace that comes with the car with the wheel nuts torqued to that extreme.