With or Without Wheel Covers? High Res Comparo Photos

While I don't like the look of the "alloy hubcaps" particularly, I'd give weight to the fact that without them there's increased drag. Why else would Toyota go through the trouble of designing and manufacturing the Prius, and other vehicles, with those "bottom covers," including the Prius's oil-drain hatch?

This reminds me of the (BSA) Cub Scouts' Pinewood Derby, where kids (okay, their dads, and some moms) will do any little thing to ostensibly give their chunk of wood an advantage... Toyota engineers have found "The Fluke," and it's these wheel covers!

 

Maybe the wheel covers push the Gen 3's coeff of drag number down to the 0.25 where they can say it is the lowest in any current mass production car. Without it, it might be 0.26, and so while it is uglier, the bragging rights are worth it to Toyota.

 

I think I am going to have to explain that in Britain we do not have the same range of Prius models as you do in America.

3 models only !

We have the T3 ( bare model with the prementioned 15" alloys and ugly plastic covers ).
The T4 with 17" alloys, ( not 16" - sorry ), that are smooth with five spokes, ( NO plastic cover )

The T4 Spirit with the same smooth five spoke 17" alloys but with sat nav and a few other refinements.

What I cannot understand is why Toyota cannot put "smooth five-spoked" 15" wheels on the T3 entry model ?

As they all - in Britain - use the same power train and the same aerodynamic body in all three models why don't they just put a nicely finished 15" alloy like the other alloys on the other models instead of going to the trouble to put an inferior 15" alloy covered by a pugly plastic cover on this model ?

I really cannot see that the false-economy of a cheap and nasty 15" alloy on the T3 covered by flipping plastic does ANYTHING for the car even if it does, ( which I don't believe ), make this aforesaid cheap and nasty alloy more aerodynamic.

 

Speculation on Toyota's purpose for putting the plastic wheel
covers on the Prius predates the Gen III model by, oh, maybe
eight years. As far as the Gen II goes, there has been some
anecdotal reports alleging that they must be an aerodynamic aid
because an individual's FE suffered a few 1/10ths reduction when
the wheel covers were removed. On the other hand, many posters
report no FE reduction whatsoever when they removed the covers...
me included.

Even if there is a FE contribution, it is most probably out in the third
decimal place of Cd, i.e. 0.00X. I have never seen any data on this
supported by serious, scientific test results. So truthfully, who's to
say, one way or the other? Vis-a-vis aerodynamics, I think that the
best that can be said about the wheel covers is, "they may make
the alloy wheel appear more aerodynamic to some people."

Members of PRIUSchat are Prius enthusiasts. We are not only a
small proportion of all Prius drivers, but we tend to look at, think
about, and speculate about the smallest details about the cars we
drive. I believe that the vast majority of Prius drivers could care less
about aerodynamics, and they aren't about to change anything
about the outside of the car on a whim -- they would however make
small changes to the interior.

These many "typical" owners would find it strange to buy a car with
alloy wheels that would suffer unsightly, although not necessarily
damaging, scuffing, scratching, and gouging from contacting the
curb in a botched attempt to parallel park -- "curb rash." It would
upset these people if they had to separately buy protection for easily
forseeable damage to their expensive alloy wheels. It would be in
Toyota's long term self-interest to keep this large numbers of Prius
owners happy...

Voila! OEM wheel covers for protection, not aerodynamics.

I could be convinced otherwise, but it's going to take more than "He
said, She said," and random, sporadic individual owner's scientifically
unsupported experiences... including mine! In my case, I will
readily admit that taking off the wheel covers is purely a subjective
matter of "style." I like the looks. There is no accounting for "taste."

Of course YMMV, and life goes on.

 

Your logic (protection for the masses) would apply to all Toyota vehicles that come with alloy wheels. Does Toyota put such plastic covers on all such vehicles?

 

The official word from Toyota is it's for aerodynamic purposes.

 

And I cannot understand this idea at all !

As someone above said...ALL expensive alloy wheels are at risk of "kerb-rash" and nobody EVER thinks of covering these wheels with plastic in order to "protect them".

With that argument in mind I cannot accept that that was Toyota's agenda when they tarted up the "alloy" 15" wheels with a plastic wheel cover. In fact I have seen a few plastic wheel-covers on ordinary steel wheels that have been "kerbed" and they look awful as they are very easily damaged in such an event.

If we agree that Toyota did not put these plastic covers on top of alloy wheels for aerodynamic purposes then they must be there for aesthetic reasons. After all, damage that is suffered on alloy wheels after "kerbing" them is done when the alloy sticks out past the tyre.

Maybe THAT is the real reason for putting plastic covers over cheap and nasty alloy wheels eh ?

Either that or the cheapo 15" alloys that are on the bottom of the range Prius are just not well enough finished to withstand corrosion from road-water, dirt or salt. Many VERY expensive alloys in the past have quicky corroded in this way.

I know one thing....Plastic wheel-covers definitely detract from the general beauty of the Prius and maybe Toyota should think again about these cheapening plastic covers.

Rant concluded !

 

I cannot take that leap of faith.

Besides, as others have pointed it out, Toyota's official word is that the reason is aerodynamics. I'll believe them unless there's credible evidence that they are lying.

 

Unlike alokeprasad, I am unwilling to simply accept Toyota's word that the plastic covers on the bare T3 model are there for aerodynamics alone.

Every person that has previously bought a bottom-of-the-range model of ANY car has accepted that for cheapness of purchase and greater profits to the manufacturers or the retailers the plastic covers over steel wheels are what is the norm. That is one of the negative qualities of buying the cheapest model available.

This surprising move by Toyota to put a plastic cover over a MAGNESIUM ALLOY wheel seems simply inexplicable other than that the wheel under that pugly plastic cover is an inferior and therefore cheaper one.

The idea that that plastic cover has ANY amount of streamlining effect to me is ridiculous as even if this was to be the case the efficiency increase would be minimal against one of the uncovered 17" alloys.

I am certain-sure that the difference in manufacturing cost between the present HIDDEN mag-alloy on the bottom-of-the-range Prius cannot be very much between that cost and the cost of manufacture of a 15" mag-alloy of the same design as in the 17" wheel - PLUS the cost of making a plastic cover to go over this present inferior alloy.

I do take the point from Tideland Prius that dirt and salt etc could get trapped between the plastic cover and the mag-wheel if the cover was not taken off regularly and any corrosion chances were dealt with timeously.

ANOTHER good reason for not having plastic covers on magnesium alloy wheels I think !

 

They could have chosen magnesium alloy instead of steel to reduce the weight of the wheels.
Having done that, they chose a wheel design that used the least amount of metal (however light) but that increased the Cd by a small amount. They then used the plastic cover to cover up the spokes and lower the Cd some. Not much, but enough to get the bragging rights.

That's my story and I'm sticking to it

 

This should be a question put to TEAM Prius
And if they do not answer they are :ban:

 

Of course you are welcome to your opinion Alokeprasad and I agree that they probably DID choose mag-alloy for that cheapo wheel to save weight as that all goes to make up the drag-coefficient as well as keeping prices down for this bottom-of-the-range Prius.

I just feel that they have cheapened a beautiful car by sticking $20-for-four plastic covers on a mag-wheel....... Don't you ?

I accept that all people have differing opinions online and I have not yet heard an argument that effectively explains why Toyota should cheapen a very beautiful car by sticking plastic covers over a mag-alloy wheel.

While I have heard some reasons for doing that I still think that Toyota should think again if they do not want their T3 Prius to be rated as downmarket and nasty by that single bad act.

Yes, steel wheels CAN be left bare on some 4X4s and pickups and in the past sticking a plastic cover over steel wheels WAS simply meant to tart up the bottom-of-the-range models but vehicles that are bought with bare - even painted - "steelies" and stainless steel wheels are usually work-horses and you NEVER see plastic covers on work-horse vehicles as they would not last ten minutes in a work environment.

I can only surmise that that pugly plastic cover on the Prius T3 wheels is either for "tarting up" purposes or for covering a cheapo and inferior mag-wheel while saving a tiny amount of DC weight.....and money.

Aesthetically, the idea does not work in my opinion and the tiny amount of decreased DC of the lighter - if cheapo - mag-wheel hidden by that plastic cover does not merit the combination of the two.

I would have rather that they had powder-coated the mag wheel if they wanted to protect it rather than sticking a plastic cover on it that will fall off at the first hard corner.

Oh and BTW.....

Could anybody post a close-up photo of one of these 15" alloy wheels WITHOUT the plastic cover on as I have tried everywhere to find such a picture without success.

 

Here is a horribly dirty iPhone photo of my wheels right after taking off the cover and popping on the center caps. Even with less than 1k miles the grime was already building up under the area where the cover snapped to the wheel.

Having had a 2005 with the partial wheel cover I'm sure they did it for aerodynamics.

I'm pretty impressed with the look of the wheels and feel like I had a little secret bonus once I popped the covers off.

 

Hi JB KC...and thanks for the photo !

As Toyota - for some reason - do not want to show a picture of that hidden wheel on ANY of their websites and it is almost impossible to find one anywhere else that has the plastic cover on the T3 15" wheel removed, this suggests to me that Toyota just do not want interested parties like me seeing this wheel in all of its bare glory.

I do remember looking at an older, ( 2008 ), model of the bare T3 Prius at my local dealer - when I was first shopping around for a new car - and at that time I looked through the plastic cap and saw a bare STEEL wheel. While I was not impressed by this at the time I thought that Toyota might - in the intervening period - at least try to improve on a tarted up-steel wheel.

IT appears that all they have done for the 2009 and the 2010 bottom-of-the-range T3 Prius is exchanged the hidden steel wheel for a hidden cheapo alloy wheel - at least in Britain.

While I seem to be getting bogged down with this point I can assure you - and anyone else that is reading this - that just because Toyota have made this quality boo-boo does not mean that I have been put off buying a new bottom-of-the-range Prius T3 in July.

I will probably just privately buy a really aerodynamic set of decent mag wheels for my new car and to hell with the cheap and nasty entry level wheels on the bare T3. :bump2:

 

When have you ever seen a manufacturer post images of a model that comes with a wheel cover without that cover? Nowt unusual in that.

And IIRC, all the GENII Prius had the same 16"mag alloy wheels with plastic covers regardless of trim level and not steel?