Ford Kuga - Downsize Alloys & Winter tyres.

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Sat 12 Nov 2011 19:36
Ford Kuga - Downsize Alloys & Winter tyres. - ady954

Hi,

I own a 2010 Kuga with 19"alloys. The tyres fitted are 235/45/19 Bridgestone Dueller HP.

I have bought a spare set of aftermarket 17" alloys with 235/55/17 winter tyres fitted in readiness of a winter as severe as last year.

I have changed the rim size because the 17" winter tyres are easier to get hold of and far cheaper to buy.

It has been suggested to me that by dropping the rim & tyre size, i will have to have the car management system recallobrated to ensure the ABS, speedo, ect function correctly. Is this correct or is the Ford dealership trying to have me over for more cash?

Thanks.

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Sat 12 Nov 2011 21:56
Ford Kuga - Downsize Alloys & Winter tyres. - RT

The limiting factor on downsizing the rim for winter tyres is the brake size.

If you've changed all 4 tyres then ABS and ESP won't be affected at all.

235/55R17 are very close to 235/45R19 so the speedo will be barely affected - and it won't be totally accurate as standard.

Your Ford dealer is trying to bend you over

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Sat 12 Nov 2011 22:00
Ford Kuga - Downsize Alloys & Winter tyres. - gordonbennet

There is a difference of 0.55% less in the winter tyre size, according to the tyre calculator i used the new tyres will be showing a speed of 69.61 mph if your summer tyres show a genuine 70mph, hardly worth bothering with.

Few things to bear in mind though, have you offered the wheels up and made sure you have enough clearance for brake calipers etc and check for no problems on full lock, do you have the correct length wheel bolts, or are nut or bolt seats of the correct taper or curve.

Lastly is the size you are going to use a standard size for you car, you should let your insurance company know for information purposes anyway, just in case.

edit, RT got in first, spot on.

Edited by gordonbennet on 12/11/2011 at 22:01

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Sun 13 Nov 2011 00:32
Ford Kuga - Downsize Alloys & Winter tyres. - ady954

Hi,

thanks for the replies, I feel much relieved. The alloys are new and are specific to the Kuga. I have offered only one of the wheels up to check. Never tried full lock though. The kuga comes from the dealership with 3 wheel size options, 16,17 & 19. I checked with the spec list and the 17" wheel & tyre size is 235/55/17. I was led to believe by the Ford dealership that the management system of the Kuga is calebrated by them for each specific rim/tyre size. They suggest that i need to have the car gearing ratio calibrated at a cost of £50. This means that i would have to have this done twice per year. When i swap the winter tyre/rim back to the 19" in springtime at a cost of £100 p/a. The new rims were supplied with specific studs, it is not the clearance I'm worried about, but the gearing ratio.

Thanks again

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Sun 13 Nov 2011 07:49
Ford Kuga - Downsize Alloys & Winter tyres. - jc2

Your driver's handbook should give you the APPROVED size for winter tyres.

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Mon 14 Nov 2011 09:36
Ford Kuga - Downsize Alloys & Winter tyres. - ady954

jc2,

No mention off approved winter tyre sizes in handbook. Only tyre preasures & chain applications.

I have the info I require now thanks to all.

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