QuestionHello - I am currently driving a 2008 BMW 335i with 225/40 R18 up front and 255/35 R18 on the back. All are runflats. I'm in New Hampshire and want to swap to a set of winter tires and wheels.
I've been getting local prices and looking on tirerack.com. I want to stay as close as OEM as possible but need to be on a budget of some degree.
I want to go with the Blizzaks RFT but they are not made in 255. Got a quote for a set of Hankook's but have read horrible reviews about these.
To my question - - - I would like to simply get a set of Bridgestone Blizzaks, 225/40's all the way around. Do you see any issue with going with a slightly narrower rear snow tire? From what I have read, it should be better for snow in general, but I'm concerned about some other aspect I may have not thought of (ABS??). Thanks in advance for any help. Getting cold up here and racing to make the swap.
AnswerDear Ed,
Thank you for using AllExperts.
How did you know to consult an expert with the same car as you!
We have a dilemma here as I feel Bridgestone has some obligation to make winter runflat tires available for (our) car. I also checked The Tire Rack, 1010tires, and Discount Tire Direct. Only the Hankook tires seem to be available.
Let's look at the overall dimensions first:
255/35R18 = 25.31"
225/40R18 = 25.39"
Pretty close. I'm not concerned with the diameter difference.
Our rear 255/35R18 original tire is a "load index" 90. "Load index" is a numerical value associated with the tire's max. load capability. We wouldn't want to apply a tire with a lower number such as '89.' The 225/40R18 is available on the market in both 88, and 92 load index (possibly 83).
A 225/40R18 with '92' load index would carry the load.
Here are my concerns:
Winter tires tend to decrease the handling properties of a vehicle, even if we use the exact same size as the original size. Using a 225/40 on the rear may cause a certain amount of "over steer" to your 335i...to a degree that may be uncomfortable (oversteer is the tendancy of the rear-end to slide out in turns).
I will make this bold proposal:
Please contact Bridgestone Consumer Relations Dept. (800 number on your tire warranty) and explain your dilemma. Ask them if it would be permissable to use NON runflat tires if you also purchased a Conti "Comfort Kit."
http://www.tirerack.com/accessories/detail.jsp?ID=38
Some BMW models came with NO runflat tire and no spare tire (M3 for example), but were equipped with this kit (it is a combination air pump and tire sealant). I used it successfully several times with my former E46 M3. It is only good for normal nail punctures, however.
Contact me again with any questions...but do call Bridgestone.
