Differing Tire Size

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As my car suffered a tire blow out on Friday, I'm wondering something.

I have 195/60/14 all around, but my spare is a 195/70/14.

Am I doing any slight (or otherwise) damage to the gearing/differential? As I understand it, the differential is able to cope with changes of the sort, but am unsure if it is doing any long term damage as the difference is no longer only in cornering.

I'm having to wait to buy new tires...shopping for a wheel/tire combo on ebay as it seemed a good time to upgrade to some bigger wheels...15's and possibly even 16's.

posted by  BavarianWheels

I'll start by assuming that you have the mixed tires on the rear axle based on your question. Put the oddball on front ASAP.

The difference in diameter between the 195/60-14 and the 195/70-14 is about 1.5", depending on the manufacturer. That means the smaller tire is rotating about 60-90 more times per mile than the bigger tire. If you are only going for very short trips a few times you can get away with it, but you will slowly work your differential to death.

Here's the kicker. If you have any type of limited slip feature in your differential you will kill it in short order. Either way not a cheap fix on a Bimmer. One last thing, I highly recommend http://www.tirerack.com for your purchase. If you buy a wheel and tire package they'll come mounted and balanced with valves and lug bolts. I've used them for years.

Edit: moved to R&M

posted by  vwhobo

just a random Mod. question but where did BW put the post originally?

posted by  SuperJew

BW, you can't go wrong doing business with tirerack.com. I've used them for years. They are one of the ,if not the best tire/wheel stores on or off the net. They bust their butt before and after the sale. THIS IS NOT AN AD!

posted by  lectroid

yeah i know lectroid.

posted by  SuperJew

Thanks!! Doing that in the morning first thing!!

Sorry for posting in wrong area...I was assuming (there's that word again) that questions directed towards vwhobo were to be placed in the "Gearhead Garage" area.

posted by  BavarianWheels

You are most assuredly welcome. I think there might be a little confusion on everyone's part, including me. Direction from management please. 8O

posted by  vwhobo

ill act in mangement....only Gearhead Garage related questions to vwhobo are put in Gearhead Garage. all other vwhobo, or anyone, questions go here, in Repairs & Maintenance

posted by  SuperJew

Otherwise you'd have nothing to moderate?... ;)

::outta jealousy::

posted by  BavarianWheels

har har har, very funny BW.

posted by  SuperJew

So uh, when were you gonna show us your new reeimms and and tires? Or are you gonna be a one hit wonder on this.

posted by  vwhobo

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PM'd you, vwhobo.
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posted by  BavarianWheels

it doesnt matter as long a your going strate

posted by  AutoPro

Welcome to 2 years ago, moron.

posted by  Benson

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