Merc cruise control

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Fri 20 May 2005 14:06
Merc cruise control - Al 42
Driving to an MB dealer 20miles away to have the brake fluid changed (half the price of my local one) I noticed cruise control wouldn't work on the motorway - or indeed above 55mph. I asked the dealer to check it over and they said this was due to the wrong tyres being fitted (205 55's on 16 inch rims) - these are the standard MB wheels and the tyres were fitted by an MB dealer! Before I take this up with Mercedes could anyone give me a guide as to what the problem may be - is there a sensor perhaps that's been left off?
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Fri 20 May 2005 14:42
Merc cruise control - Aprilia
Most probably due to wrong sized tyre or one or two tyres being more worn than others. The MB cruise control system is very sensitive to tyre diameter.
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Fri 20 May 2005 15:00
Merc cruise control - Al 42
Thanks for this advice, the back tyres are new with only a few hundred miles on (Continentals)- the fronts are about half worn and I think Champinos or something. Do the front and back tyres need to be the same make? They're all 205 55 16's by the way.
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Fri 20 May 2005 17:38
Merc cruise control - Aprilia
They need to be the same *rolling diameter*, to within a couple of percent.
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