# Why the dented spare tire covers? **URL:** \ **Category:** Factual Questions\ **Created:** [July 9, 2009, 5:18pm UTC](https://boards.straightdope.com/t/why-the-dented-spare-tire-covers/502471 "2009-07-09T17:18:11Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![Dinsdale](https://avatars.discourse-cdn.com/v4/letter/d/97f17d/32.png) [@Dinsdale](https://boards.straightdope.com/u/Dinsdale)\ **Post date:** [July 9, 2009, 5:18pm UTC](https://boards.straightdope.com/t/why-the-dented-spare-tire-covers/502471/1 "2009-07-09T17:18:11Z")
Anyone know why so many metal spare tire covers on vans and SUVs have a boomerang-shaped dent in them? First time I noticed it I thought they had all been in similar accidents, but they appear to be too common for that. Does the dent serve some structural purpose? Is it purely aesthetic? Sorry, couldn’t quickly google up an image. ---
**Author:** ![Mister\_Rik](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mister_rik/32/491_2.png) [@Mister\_Rik](https://boards.straightdope.com/u/Mister_Rik)\ **Post date:** [July 9, 2009, 6:25pm UTC](https://boards.straightdope.com/t/why-the-dented-spare-tire-covers/502471/2 "2009-07-09T18:25:23Z")
My guess is it’s there to add rigidity to the cover. A flat sheet of thin metal isn’t going to be very rigid, but put a bend in it (witness corrugated metal roofing/siding) and it instantly becomes much more sturdy. ---
**Author:** ![Balthisar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/balthisar/32/2825_2.png) [@Balthisar](https://boards.straightdope.com/u/Balthisar)\ **Post date:** [July 9, 2009, 11:42pm UTC](https://boards.straightdope.com/t/why-the-dented-spare-tire-covers/502471/3 "2009-07-09T23:42:51Z")
Google images almost immediately autofilled “spare tire cover” for me, but I can’t find an example of what you’re talking about. It could be style, or like **Mister Rik** points out, a means to prevent “oil-canning” (since structural rigidity alone isn’t a factor in a non-structural car part). And yes, “oil-canning” is the technical term in the automotive industry for the annoying sound of a flat piece of sheet metal popping in and out all the time – like an old-style oil can. ---
**Author:** ![YamatoTwinkie](https://avatars.discourse-cdn.com/v4/letter/y/cc9497/32.png) [@YamatoTwinkie](https://boards.straightdope.com/u/YamatoTwinkie)\ **Post date:** [July 9, 2009, 11:51pm UTC](https://boards.straightdope.com/t/why-the-dented-spare-tire-covers/502471/4 "2009-07-09T23:51:20Z")
OP is probably thinking of the Toyota [RAV-4](http://www.toyota.com/rav4/photo-gallery.html), which has a rather distinctive boomerang-looking “dent” in the rear spare tire cover. ---
**Author:** ![Dinsdale](https://avatars.discourse-cdn.com/v4/letter/d/97f17d/32.png) [@Dinsdale](https://boards.straightdope.com/u/Dinsdale)\ **Post date:** [July 10, 2009, 1:04pm UTC](https://boards.straightdope.com/t/why-the-dented-spare-tire-covers/502471/5 "2009-07-10T13:04:44Z")
> [@YamatoTwinkie](#): > > OP is probably thinking of the Toyota [RAV-4](http://www.toyota.com/rav4/photo-gallery.html), which has a rather distinctive boomerang-looking “dent” in the rear spare tire cover. That is the “dent” - but keep your eyes open while on the road - it is not unique to RAV4s or even Toyotas. And I thought it was likely related to rigidity, but was surprised that I did not see any different patterns than the boomerang. May be as simple as there are very few manufacturers of these covers who supply all car makers. ---
**Author:** ![Bijou\_Drains](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bijou_drains/32/2814_2.png) [@Bijou\_Drains](https://boards.straightdope.com/u/Bijou_Drains)\ **Post date:** [July 10, 2009, 1:31pm UTC](https://boards.straightdope.com/t/why-the-dented-spare-tire-covers/502471/6 "2009-07-10T13:31:52Z")
If you look at cars all sides are not one simple flat piece of metal - they have ridges, creases, etc. I guess they felt the same should apply to the tire cover - they don’t want a flat piece of metal there either. ---
**Author:** ![AskNott](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asknott/32/5790_2.png) [@AskNott](https://boards.straightdope.com/u/AskNott)\ **Post date:** [July 10, 2009, 1:43pm UTC](https://boards.straightdope.com/t/why-the-dented-spare-tire-covers/502471/7 "2009-07-10T13:43:35Z")
There are also lots of unintentional dents in spare tire covers. Drivers of other cars don’t allow for that extra 8 inches when the back up in parking. ---
**Author:** ![HorseloverFat](https://avatars.discourse-cdn.com/v4/letter/h/8e8cbc/32.png) [@HorseloverFat](https://boards.straightdope.com/u/HorseloverFat)\ **Post date:** [July 10, 2009, 1:58pm UTC](https://boards.straightdope.com/t/why-the-dented-spare-tire-covers/502471/8 "2009-07-10T13:58:46Z")
The exterior of the car really has nothing to do with structure. Its all styling. The big curves in my door and on my wheel cover is just there so the car doesnt look boring. I think youre just noticing a fad in design. ---
**Author:** ![Telemark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/telemark/32/372_2.png) [@Telemark](https://boards.straightdope.com/u/Telemark)\ **Post date:** [July 10, 2009, 2:11pm UTC](https://boards.straightdope.com/t/why-the-dented-spare-tire-covers/502471/9 "2009-07-10T14:11:02Z")
> [@HorseloverFat](#): > > The exterior of the car really has nothing to do with structure. Its all styling. Not completely true. As stated above some creases and curves are necessary to add strength to the panels. ---
**Author:** ![Balthisar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/balthisar/32/2825_2.png) [@Balthisar](https://boards.straightdope.com/u/Balthisar)\ **Post date:** [July 10, 2009, 2:58pm UTC](https://boards.straightdope.com/t/why-the-dented-spare-tire-covers/502471/10 "2009-07-10T14:58:19Z")
> [@Telemark](#): > > Not completely true. As stated above some creases and curves are necessary to add strength to the panels. All curves and creases are that for that reason. There’s no such thing as an absolutely flat surface on any modern, mass-produced car. Well, yeah, if you start approaching 0 as a limit, then there’s flatness, but in human terms, there’s none.