Strangest thing happened to me tonite

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Discussion Overview

The discussion revolves around an incident where a participant's front fender fell off while driving. Participants explore the possible reasons for this occurrence, including vehicle design, potential previous damage, and the condition of the car's fasteners. The conversation touches on aspects of automotive safety and repair, as well as personal experiences related to vehicle maintenance.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant describes their experience of the front fender falling off while driving, questioning if this is a common occurrence.
  • Some participants propose that fenders are designed to detach easily in low-speed collisions, suggesting that missing or worn fasteners could lead to such an event.
  • Others argue that the speed at which the participant was driving (50 mph) is significant and may not align with typical design expectations for fender detachment.
  • A participant questions the implications of fender design on pedestrian safety and the rationale behind using easily breakable materials.
  • There are inquiries about the potential for previous damage or shoddy repairs contributing to the fender's detachment.
  • Some participants discuss the possibility of stress corrosion cracking affecting the fasteners, particularly in regions where roads are salted.
  • Another participant shares a personal anecdote about being hit by a car, which introduces a different perspective on vehicle safety and impacts.

Areas of Agreement / Disagreement

Participants express a range of views regarding the reasons for the fender detachment, with no consensus reached on the exact cause. Some agree on the design aspects of fenders, while others question the implications of speed and previous damage. The discussion remains unresolved regarding the specific circumstances leading to the incident.

Contextual Notes

Participants note various factors that could influence the fender's detachment, including the age of the vehicle, the condition of fasteners, and potential impacts from other vehicles. There are also references to regional differences in vehicle maintenance practices.

pentazoid
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While I was driving my car, all of a sudden my front fender falls off. At first , I thought I had hit something or someone, but my front fender was not dented up , and there were no traces of blood on my fender. I think my airbags would have activated had I hit a car or someone. I got out of my car to see if I hit anyone, there was no one around my car.Miraculously , as I drove my car home , the front part of my fender did not drag under my car. I placed my fender back on the front of my car and it looks as if the car was never hit. I noticed some screws were missing . I know this kind of thing doesn't happen everyday , but is it possible that you can be driving on a road and your front fender suddenly fall down?
 
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The fenders are designed to crumple and fall off in low speed collisions (especially with pedestrians) so they are only held on with a couple of easily breakable plastic bolts or clips. It could be that yours are missing or have perished.
 
mgb_phys said:
The fenders are designed to crumple and fall off in low speed collisions (especially with pedestrians) so they are only held on with a couple of easily breakable plastic bolts or clips. It could be that yours are missing or have perished.

low speed collisions? I was going 50 mph.
 
They are designed to break off easily (as in low speed collisions) so are only held on weakly. So going over a small bump at 50mph might do it if the bolts are missing/worn.
 
pentazoid said:
While I was driving my car, all of a sudden my front fender falls off.
The whole bumper or just the plastic fascia?

mgb_phys said:
The fenders are designed to ... fall off.
Why? How does this facilitate pedestrians getting less hurt?
 
DaveC426913 said:
Why? How does this facilitate pedestrians getting less hurt?
The plastic bumpers are supposed to crumple in a low speed impact to stop the pedestrian hitting the boy of the car (or at least slow them down) so the bumpers are made of easily breakable plastic - including the clips that hold them to the boy.
 
mgb_phys said:
They are designed to break off easily (as in low speed collisions) so are only held on weakly. So going over a small bump at 50mph might do it if the bolts are missing/worn.

I have a question. Once the fender is broken off, how long do you think it will take to fix it?
 
pentazoid said:
I have a question. Once the fender is broken off, how long do you think it will take to fix it?
It would depend on why the fender fell off. If the part that holds the screws/bolts to the car is damaged to the point that it is useless, a new fender may be needed. If it's just a matter of bolting it back on, that shouldn't take long at all.
 
mgb_phys said:
The plastic bumpers are supposed to crumple in a low speed impact to stop the pedestrian hitting the boy of the car (or at least slow them down) so the bumpers are made of easily breakable plastic - including the clips that hold them to the boy.

:smile: What the heck?! :smile:

Where the heck do you live? Up in the North woods, a lot of people drive around with deer strapped to their cars, but... :smile:

Is this a UK-US difference in language?

And as to the original post, do you mean the front bumper? Or some sort of plastic trim on the fender? (I can't really envision either the entire front bumper or the entire fender falling off). Post a pic of what you're talking about.
 
  • #10
BobG said:
:smile: What the heck?! :smile:

Where the heck do you live? Up in the North woods, a lot of people drive around with deer strapped to their cars, but... :smile:

Is this a UK-US difference in language?

And as to the original post, do you mean the front bumper? Or some sort of plastic trim on the fender? (I can't really envision either the entire front bumper or the entire fender falling off). Post a pic of what you're talking about.

No , I just mean my whole front fender. My headlights work just fine and are intact, my front fender is busted.
 
  • #11
pentazoid said:
No , I just mean my whole front fender. My headlights work just fine and are intact, my front fender is busted.

No, I've never heard of anyone's fender falling off. Is this a used vehicle that might have been in an accident? Some shoddy repair work might be at fault. Perhaps they stripped the screws/bolts when taking the fender off, but still replaced them even though they were no longer doing anything?

Normally, it's very easy to dent a fender and have a small dent bend the entire fender in odd places since it's designed to crumple and absorb energy. Even in an accident, it's rare for the fender to just fall off. To come off, it usually has to be ripped off during the accident because it caught on the other car or on some stationary object (tree, guardrail, etc).

The normal repair nowadays is to order a brand new fender (or get an undamaged one from the junk yard and repaint it). The old method of removing the dent seems to be archaic since the fender can bend and warp in spots pretty far removed from the initial damage. That also means an accident could also stress the bolts/screws in an unusual way.
 
  • #12
pentazoid said:
While I was driving my car, all of a sudden my front fender falls off. At first , I thought I had hit something or someone, but my front fender was not dented up , and there were no traces of blood on my fender. I think my airbags would have activated had I hit a car or someone. I got out of my car to see if I hit anyone, there was no one around my car.Miraculously , as I drove my car home , the front part of my fender did not drag under my car. I placed my fender back on the front of my car and it looks as if the car was never hit. I noticed some screws were missing . I know this kind of thing doesn't happen everyday , but is it possible that you can be driving on a road and your front fender suddenly fall down?
How old is the car? If one uses a car in the north or northeast where roads are salted, some fasteners (aluminum or steel) are susceptible to stress corrosion cracking (SCC), usually at the base of the head where is joins the shank.

Could someone impacted the car in a parking lot recently? That might fail some fasteners by shear, especially if they were already damaged by SCC.
 
  • #13
Where do you live? In sub zero temps, cars hitting snow balls on the road and knocking off bumpers aren't exactly unheard of.
 
  • #14
Astronuc said:
How old is the car? If one uses a car in the north or northeast where roads are salted, some fasteners (aluminum or steel) are susceptible to stress corrosion cracking (SCC), usually at the base of the head where is joins the shank.

Could someone impacted the car in a parking lot recently? That might fail some fasteners by shear, especially if they were already damaged by SCC.

my car is only 4 years old. Just bought it last year, so its used. I am think that while I was in a parking lot , somebody possibly could have hit front bender and displaced the screws that were holding my fender together. I think as I continued to drive my car, the screws that were loosely holding my front fender together displaced completely and then the fender just fell off. The fender fell off my car while I was driving.
 
  • #15
The weirdest thing happened to me today. I was walking my dog along the side of the road when all of a sudden this car doing about 50 mph ran right into me. I was knocked into a thick bunch of bushes and it took forever for anyone to find me. I've got two broken legs, my dog is dead and if I ever find that sob that hit me...
 
  • #16
tribdog said:
The weirdest thing happened to me today ... it took forever for anyone to find me.
Not 'today'. You were lying in that bush in a coma for seven days.
 
  • #17
mgb_phys said:
The plastic bumpers are supposed to crumple in a low speed impact to stop the pedestrian hitting the boy of the car (or at least slow them down) so the bumpers are made of easily breakable plastic - including the clips that hold them to the boy.
"Boy"?
tribdog said:
The weirdest thing happened to me today. I was walking my dog along the side of the road when all of a sudden this car doing about 50 mph ran right into me. I was knocked into a thick bunch of bushes and it took forever for anyone to find me. I've got two broken legs, my dog is dead and if I ever find that sob that hit me...
oh THAT boy.
 

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