Changing wheel sizes

[ChrisJohn]

I have an new Auris TSS Hybrid Excel that came with 17" alloy wheels fitted as standard.  I would like to fit 16" with Michelin Cross Climate tyres.  My Toyota dealer states that he cannot find a Toyota 16" wheel listed for my car (even though 16" is the standard alloy size for the other grades other than the basic 15" steel).  If I fit non Toyota OEM wheels will I have any Toyota warranty issues?  Does anyone have any recommendations for a 16" alloy replacement for the Toyota originals?   I know I will need TPMS valves and assume these will register without problems? 

[FROSTYBALLS]

As regards the warranty, this obviously won't cover non-toyota wheels and may not cover issues with the tmps (as the sensors are fitted to non OE wheels). If Toyota wheels are bought these would probably be covered by a 12 month warranty rather than the new car warranty, as they weren't fitted when the car was  ordered.

Check the effect on the speedometer of the proposed wheel/tyre combination using one of the various tyre change websites. It is illegal for a speedometer to under read, and over reading has limitations.

Check with your insurance company as to whether they consider the change a modification - may incur an additional premium if they do.

Do you need to update your profile to include the Auris.

[16_Auris_HSD]

Toyota UK on their blog claim that for some technical unexplained reasons Excel trim cannot sit on wheels smaller than 17 inch ("as confirmed by the technical department" is the excuse). If you look at other European markets most offer top specifications with 16 inch wheels as standard and the 17 inch that we get is an optional upgrade.

So unless our cars are different because of RHD I'd say there should be no reason not to go 16. Except for them potentially refusing warranty work since the official statement is that 17 inch is the lowest allowed size for Excel trim.

[Heidfirst]

2 potential reasons:

1) which I doubt is applicable to you - on my last Avensis the 2.2 had bigger front brakes than all other engines so 16" wheels  wouldn't fit due to the discs although they would fit other Avensis.

2) much more likely - the car hasn't been homologated with them (my Avensis T Spirit hadn't been homologated for the wheels that I use for Winter even though they came from a mechanically identical Avensis T4, which they had been homologated for). In that case as long as your insurance company is aware & OK that you are using different wheels you should be OK (although if you were in an accident it would be a potential avenue of attack for the prosecution).

[ChrisJohn]

Thanks for the replies.  I have now updated my profile although it would be good if you could add more than one Toyota model easily. I still drive the RAV whilst my wife is the main user of the Auris.

I did ask the question on the Toyota Blog before ordering the car but as there were features on the Excel that we particularly wanted, I paid the extra hoping to be able to change the wheels sometime later. The answer that I received from the Toyota spokesperson stated: "Thank you for getting in touch with us. The 17″ wheels for the Auris are standard to that model and you can’t order the car with 16” wheels from factory. However, you may be able to get 16” wheels as accessories and get them fitted by your local Toyota dealer."  This contradicts the information quoted by 16_Auris_HSD so I would be interested to pursue this with Toyota. Some information to help me find that bit of the blog would be useful.  My question appeared in the Auris section on 8th August.  I am aware that to buy new Toyota 16" wheels might be prohibitively expensive but I would at least like a definitive answer if this is technically possible without compromising the car's integrity in any way.

[16_Auris_HSD]

http://blog.toyota.co.uk/whats-changed-2015-toyota-auris

Search for a comment from Robert Forse and subsequent responses from Toyota.

[Heidfirst]

That states " Unfortunately 16″ wheels cannot be fitted due to technical reasons – the steering rack does not allow for 16″ wheels to be fitted safely. "

I would be surprised if the steering link on the Auris Excel hybrid differs from that fitted to lower grade Auris hybrids, which can take 16" wheels & indeed ares sold as standard with those.

[eygo]

why can't toyota just be upfront and say why they cant be fitted safely rather than saying technical reasons.

what harm would be done if the technical reason could be made public.

[16_Auris_HSD]

That's what I don't get either. Excel is somewhat different from other specifications in terms of equipment so perhaps there is a real reason why RHD cars can't sit on wheels smaller than 17. CoC should show the homologated wheel sizes for a given car.

[ChrisJohn]

I have posted a further reply on the Toyota blog asking for the contradiction to be clarified.  With any luck we might get a reasoned definitive answer to this question but don't hold your breath.  Apparently larger wheel sizes with lower profile tyres are seen as a premium offering by the marketing types at Toyota.  Why anyone would choose a size that is clearly too big for the car I don't know.  The handbook states that snow chains cannot be fitted with 17" wheels and the fuel consumption is quoted as 11% worse. This latter fact is apparently partly due to greater friction due to a larger area of (the wider) tyre in contact with the road.

[ChrisJohn]

It is perhaps worth pointing out that whether you have 15", 16" or 17" wheels fitted, the appropriate tyre sizes brings the wheels up to virtually identical sizes in terms of diameter and circumference so that speedometer calibrations are all the same and within normal tolerances. The figures are:

15" (6J rim) Tyre 195 65 R15 gives diameter 25" and circumference 78.4" (832 revs per mile)

16" (6.5J rim) Tyre 204 55 R16 gives diameter 24.9" and circumference 78.1" (835 revs per mile)

17" Tyre  (7J rim) 225 45 R17 gives diameter 25" and circumference  78.4" (832 revs per mile)

This means that the only real difference can be due to the width of the rims and tyres that might perhaps interfere with something on the 17" size?

[FROSTYBALLS]

Using the above tyre sizes and a tyre size calculator, the 17 and 16 are OK. The 15 gives a slight under-read, which wouldn't be legal.

[ChrisJohn]

Not quite sure why you say that as the calculator that I used on https://tiresize.com/tyre-size-calculator/ and where the figures in my post came from showed the 15" and 17" as identical. As the most common wheel size on the Auris is 16" one would assume that Toyota bases its calibration on that size and then the 15" and 17" would over read by a mere 0.36% which is well within accepted legal tolerances. Have you used a different tyre calculator ?  I guess there must be some variations in different manufacturer's tyres?  This whole area is quite new to me and I have already learned quite a lot about different aspects of car wheel sizing!

[FROSTYBALLS]

Yes, have used a UK based tyre calculator which calculates the degree of over or under reading

[ChrisJohn]

Thanks.  I thought that might be the case.  Can you point me to the one that you used please?

[DAN@ADRIAN FLUX]

Hi,

If you did find you had any issues with your insurance for a change of wheels then please feel free to drop me a line.

Regards,

Dan.

[ChrisJohn]

Thanks for that.  I am still trying to find out what is technically feasible at the moment.  If I get to the next stage and have any insurance issues then I will make contacts.  Thanks again.

[sproutdreamer]

I am watching the outcome of this post as I may get an Auris and had thought on the grounds of comfort that if I could not get the car I want with 16" alloys & fatter tyres I could always get one with 17" and swap to 16" later - maybe not but thanks for posting this.

[ChrisJohn]

I posted on the Toyota blog asking for clarification of the apparent contradiction where one adviser has said that 16" cannot be fitted on the Excel because it would interfere with steering gear and another adviser said I could get 16" wheels as accessories. This post seems to now have disappeared or at least I can no longer find it.  I am inclined to stick with the 17" and probably fit Michelin Cross Climate tyres which are a safer option where I live in Scotland than the Dunlop summer tyres that came as new on the car.

I am still no nearer getting a definitive answer on whether smaller than 17" wheels can be safely fitted to the Auris Excel grade.

I also note that several reviewers of the Auris have remarked that, unusually, this car handles better on 17" wheels than the smaller sizes. So far I have no complaints of the way the car handles. It seems very smooth and well balanced. The lower profile than I am used to tyres are not making their presence felt.

[16_Auris_HSD]

7 hours ago, ChrisJohn said:

I posted on the Toyota blog asking for clarification of the apparent contradiction where one adviser has said that 16" cannot be fitted on the Excel because it would interfere with steering gear and another adviser said I could get 16" wheels as accessories. This post seems to now have disappeared or at least I can no longer find it.

I was wondering that too since I couldn't find it either. Give Toyota customer services a call and ask them to provide you with their official statement. This is the best approach since you can use it in the future in case of issues (if you go for 16 inch that is).

[ChrisJohn]

Thanks for that suggestion. I'll have a go at that and will report back as to how I get on.  

[Heidfirst]

3 hours ago, 16_Auris_HSD said:

I was wondering that too since I couldn't find it either. Give Toyota customer services a call and ask them to provide you with their official statement. This is the best approach since you can use it in the future in case of issues (if you go for 16 inch that is).

I am willing to bet that their official statement will be that the car is not homologated with them & therefore they don't recommend ... 

[Stefan.k]

I've got a 2016 touringsport executive (I guess that's the excel in sweden) on 17" wheels in the summer and 16" in the winter.

Ordered the car with the a set of 16" winter tires from the dealer! They didn't say anything about that it won't fit or that it'll be dangerous on 16"

Just fit what ever you want:-) 

[ChrisJohn]

I have submitted my request to Toyota customer services via email as I want a written reply. I have asked for any technical or warranty issues to be clarified.

Stefan.k thanks for your comment and It may be a bit off topic but have you noticed any differences in driving when you swap sizes in terms of handling, comfort or fuel consumption?

[16_Auris_HSD]

8 hours ago, ChrisJohn said:

I have submitted my request to Toyota customer services via email as I want a written reply. I have asked for any technical or warranty issues to be clarified.

Stefan.k thanks for your comment and It may be a bit off topic but have you noticed any differences in driving when you swap sizes in terms of handling, comfort or fuel consumption?

Keep us posted as I might be thinking of going 16 inch next year too.

From reading online (although I can't remember exactly where, I'd gone through too many articles while researching the car) 17 inch are pretty bad for economy mainly due to being wider. I do like the ride quality they offer though. Not too soft, not too stiff just about perfect.

PS Ah and yeah, just remembered that you can get 16inch steelies for top spec Auris in LHD countries!