488 Rear Wheel Fell Off!!!

A few things I notice are these.

First off, you say his torque wrench was set to 100 nm. I might recall this incorrect, but aren't the torque supposed to be either 110 or 120 nm?

Secondly. What kind of torque wrench did he use? If he used a click style wrench, that might very well be part of the issue as they are all over the place depending on twist speed etc. Garbage! Gauge or digital for proper readings.

Was his wrench a proper quality wrench? If not, or had it been abused, it might also be off. A mid level wrench will usually do if it is not used too much between loosening. But a day of using a wrench like you describe, takes a very good wrench to stay accurate. Never mind the fact that you don't even know whether or not he takes properly care of his torque wrench. Does he loosen it after each use, or is it sitting in his tool chest dialed up to the last figure he torqued etc. All these things can have a major impact on the readings.

If the lugs get loose, you need the wheel off the ground to get a proper reading in relation to how the wheel flange mates to the hub flange. I've seen examples where the wheel was first tightened down, then the car was put on the ground for final tightening so that the wheel wouldn't spin. It left the wheel ever so slightly crooked meaning it would work it self loose over time. It wasn't much. Just enough so that you could slip a piece of paper in there. Not much, but that is all it takes.

Make sure the threads are clean and there are ARP or Loctite thread lube on them. Copper grease can be used in a pinch.

But best advice is this. If you track your car, torque your own wheels unless you are familiar with the guy doing it, and you are 1000% sure he takes properly care of his tools, use them properly, and have proper tools.

Wheels coming off cars during track days are in fact incredibly common. And in most cases it is down to human error.

Last interesting thing to add here is this. A Michelin tech once told me that, it sometimes depend on the track layout which wheel will be most prone to come loose. But as he put it, most times it would be the left rear on tracks you run in a clock wise direction. A guy working for BBS I met at a car show in Germany about 15 years ago, said something similar. He also said that they recommended running 10-15% extra torque on track using quality wheel hardware.

Do your own wheels and use specific name brand fasteners you trust. Hill Engineering and ARP are my go-to manufactures.

Fact is that the stock wheel fasteners Ferrari uses, are nothing special.

 

This is blowing my mind. I just read this post and this exact same thing happened to me on my 2019 488 spider. I had just taken delivery and only four or five miles into the trip the left rear wheel fell off. Luckily we were going very slow in a straight line and wheel fell completely off of the hub (all 5 lugs) only to be held by the rotor. When I got the car home I checked the torque on the other three wheels and they were spot-on. Car has never been on the track as far as I know as it only had about fifty miles on the odometer when it happened. luckily there was zero damage to the car otherwise the dealer would have gotten it back. I will have to admit I have been paranoid about the situation ever since and now I check the lug torque almost every time I drive the car. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login

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WOW, very bizarre. Hope there is an explanation for this...

 

They don't make 'em like they used to!

I wonder if something to do with the traction control is producing some sort of odd twisting or load, which is causing the wheel lug bolts to work themselves free. I've always run Titanium lug bolts, so never had any problems myself, but I agree that's bizarre.

When in doubt, buy Titanium lug bolts, drill the heads and use safety wire!

Ray

 

Considering the car was brand new and never driven in anger, I will be honest and say that it really sounds like a wheel someone did not torque - even though the others were spot on.
Remember that bolts always have to be tightened after the first 30-50miles when running alloy wheels.
Remember to use ARP anti-seize or a bit of copper grease. Dry threads will hinder the bolt from reaching proper stretch and torque as the friction makes it difficult for the bolt to turn. Never ever encountered a fastener manufacture claiming thread lube gives false readings - it is always the opposite they say.

You really should not tighten your bolts every other day. You'll end up weakening them, and that can create a much more dangerous situation than bolts comi g loose.

If you are worried, simply replace the fasteners with a higher quality version.such as the steel or titanium bolts from Hill Engineering. Note that those don't require lube as they are coated.

 

Never happened on my 488 but I almost lost a wheel on a track with my 575 - fortunately the wheel began to move (with impressive noise) so I stopped. It was probably an incorrect tightening since the wheel had been removed (about 400 km before) for replacing the F1 pump.

 

personal dangerous experience. I've been testing if 70NM would do the trcik on my 360 challenge. There's no issue by torquing to 70NM for all four wheels.

 

This thread really spooked me. Did the OP every get to the root cause? Did the other person who had this happen also get to the root cause? Did Ferrari ever chime in?

 

I had this happen last year. 70Nm is way below, and not safe.

Here's a few things worth noting.

1. It was never 70 Nm. It was 70'ish lb.ft. or 100 Nm.

Ferrari has since changed this to 120 Nm. Look into any recent manual, being it an F8, Pista or 812 etc. all specify 120. This is important because the hub fastening hardware and its properties has not changed. I asked my dealer tech, and he said 120 Nm as well.

I spoke to one of the guys working on Corsa Pilota cars in Maranello, and he told me to always run at least 135 Nm on track. If it is the CF wheels, they need 150 Nm.

Fact is that the 100 Nm number is terribly outdated and should not be used.

Now if better hardware such as the bolts from Hill are used, they can handle more torque. Their steel bolts will yield proper stretch up at 150 Nm and their Ti bolts are good for 180.

I cannot stress enough how much 100 Nm is not enough. Just look at what Porsche and Mercedes AMG specify now. That should be a bif of a clue as to how ridiculous 100 Nm is. A Merc GTR needs 180 for example, and Porsche run between 130 for the slow stuff and up to around 180 Nm depending on model. Of course that does not include centerlock.

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Does this mean on the 458, we should be using 120 Nm, or is this only on the F8 and newer cars?


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Can you guys recommend a very good quality and reliable torque wrench to buy? Also, a great quality socket for the torque wrench as well.

I don’t want to take any chances on my 458.


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Spoke to the service manager at Ferrari Calgary. He was not aware of any update to the 488 of 120 NM. He did say it's ok to go to 110 NM though

 

Then ask him how come it is okay to use 120 on an F8, Pista, 812, Roma or SF90? Same hardware. It is right there in his WSM as well as the owners manuals. That 110 number is just a guess on his part. Ferrari now spec 120 on everything, if not fitted with CF wheels which calls for 150.

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Nothing has changed, but Ferrari upped the torque specs. Could that perhaps have anything to do with all the incidents of loose,wheels? According to my service rep, all cars with 114.3 PCD are said to be torqued to 120. That also matches with what Ferrari now spec.

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Does the 458 have 114.3 PCD?


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it happens..

 

Yes

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This is a nice wrench.


https://shop.snapon.com/product/Standard-Models-2%25-Accuracy%2FFixed-Head/1-2%22-Drive-Fixed-Head-Techwrench-Torque-Wrench-(12.5%E2%80%93250-ft-lb)/TECH3R250

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This thread is really scary. I think that I will from now on keep my Snap On torque wrench in the frunk of my Speciale and use it often. That being said, here are some other thoughts. Some of these have been mention already in this thread, and some will contradict some things said in this thread.

Any torque specification is meaningless without the lubrication of the threads and bolt head specified. My dealer told me they torque the wheel bolts to 120Nm. I assume that this is a dry torque spec, as I believe wheel bolts and nuts usually are.

If the bolts are lubricated, then the torque needs to be reduced in order to keep the same bolt stretch. Using a dry torque specification on a lubricated bolt risks over stretching the bolt. Although I agree that torquing bolts lubricated with oil or even better ARP Ultra-Torque will give a more consistent bolt stretch and clamping force, that may not be what is most important for wheel bolts.

Unlike engine bolts and other applications that are static, wheel bolts are subject to angular acceleration. If the torsional force (torque) accelerating or decelerating the bolt exceeds the static friction of the threads and bolt head in a CCW direction, the bolt will loosen. Because braking deceleration is much greater than acceleration this happens on the left side of the car. GM cars until the early ‘60s and Chrysler cars into the ‘70s had left hand threaded lug nuts on the left side of the car presumably for this reason. This whole effect is going to be worse with the left rear wheel doing ABS stops because of the shock loading of the ABS pulses. The front wheel will be well planted and will not get pulsed, at least not as much. This is why this always happens on the left rear.

In order to keep the bolts from loosening, we need to reduce the torque caused by the angular acceleration and/or increase the static friction. To educe the torque caused by the angular acceleration, we can reduce the polar moment of inertia of the wheel bolts by reducing the mass of the bolts. This should mean titanium bolts are better than steel. Any lubrication on the threads or bolt heads will reduce the static friction. This is not what we want. Dry should be much better for wheel bolts. The other way to increase the static friction is to tighten the bolts as much as possible.

In conclusion, I think that titanium bolts should be used and installed with clean dry threads and torqued to 120Nm with a quality torque wrench.

 

I agree with most of what you said, but it seems to me that lubricating the bolts allows you to obtain a higher clamping force between the wheel and hub since less of the applied 120nm torque is being lost in friction in the bolt head and threads. I agree it reduces static friction, but only in the bolt. The clamping force should be higher with a lubricated bolt at the same torque.

Could be wrong...

 

I agree that the clamping force will be higher with a lubricated bolt at the same torque. I do not agree that that is what is important here. What is more important is that the bolts don't fall out. If in fact that bolt can withstand the higher clamping force that it would have with the lubrication, the better answer would be to leave it dry increase the torque to get to that same clamping force.

 

Understood. I'm assuming that the bolt backing out is precipitated by movement between the wheel and hub due to traction control etc. as discussed previously, so I thought higher clamping force would reduce/eliminate the movement. I understand your position that higher friction in the head threads should keep it from backing out. I'm not advocating this, but Locktite is typically used in these instances.

 

Can a home point me to a link that communicates the updated 120 NM spec online?



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Page 31 in the F8 Owner’s Manual. Image Unavailable, Please Login

 

88.5ft lbs is for the f8. Are the rotor hats and wheel hub and bearings and wheel bolt parts the exact same as the 488?