[ctpolyak]

Just purchased 2018 340i 6MT M Sport w/ 19'' 704M PRFs. . . I'd like to swap the RFs for traditional tires.

Question - can I go square or are front/rear wheels different sizes with this OEM configuration (704M M Sport)? In other words, do I need to order 2 225-40-19 (Front) and 2 255-35-19 (Rear) or would 4 225-40-19 tires fit, and if so, what would drawbacks be?

I'm debating between set of all-seasons on the 19s, or staying w summer tires, and getting a set of 18'' wheels w/ a winter set-up. Moving to southern NJ in few months from NC.

Thanks for input.

[im_an_alien]

No problem doing square setup. I just picked up a second set that is 18in square with 255/40 regular summer tires, along with the factory 19in 403m with summer run flats. Also 6mt RWD. I split my time between FL and NH but the car doesn't see snow so I don't really have a winter setup. Might sell the 403m wheels, car rides better with the 18s.

[chowser51]

Get some 18” winter setup for the NJ potholes.

Or look into all weather tires like the Michelin CrossClimate2 or Nokian WR G4.

[thejeremyman9]

Originally Posted by ctpolyak

Just purchased 2018 340i 6MT M Sport w/ 19'' 704M PRFs. . . I'd like to swap the RFs for traditional tires.

Question - can I go square or are front/rear wheels different sizes with this OEM configuration (704M M Sport)? In other words, do I need to order 2 225-40-19 (Front) and 2 255-35-19 (Rear) or would 4 225-40-19 tires fit, and if so, what would drawbacks be?

I'm debating between set of all-seasons on the 19s, or staying w summer tires, and getting a set of 18'' wheels w/ a winter set-up. Moving to southern NJ in few months from NC.

Thanks for input.

You need to know the width of your rims. If they are 8'' up front you dont want to run a 255 on that. If they are staggered 8/8.5 rims front and rear i recommend 245/35/19 and 255/35/19.

https://f30.bimmerpost.com/forums/sh....php?t=1678451

[johnung]

Originally Posted by ctpolyak

Just purchased 2018 340i 6MT M Sport w/ 19'' 704M PRFs. . . I'd like to swap the RFs for traditional tires.

Question - can I go square or are front/rear wheels different sizes with this OEM configuration (704M M Sport)? In other words, do I need to order 2 225-40-19 (Front) and 2 255-35-19 (Rear) or would 4 225-40-19 tires fit, and if so, what would drawbacks be?

I'm debating between set of all-seasons on the 19s, or staying w summer tires, and getting a set of 18'' wheels w/ a winter set-up. Moving to southern NJ in few months from NC.

Thanks for input.

Welcome to South Jersey!
IMO I'd keep your staggered setup and order yourself a set of summer Michelin Pilot Sport 4S.

You have plenty of time to keep a look out for a used set of 18" square 400M wheels, usually $300-$600 for a set. (All 8.0"x 18", not the staggered rear 8.5") To be used as a winter set. Usually the temperatures get down to the 40's and I need to swap on my winter tires in late November/ early December. Usually the summer tires can go back on around now, late March/early April.

Winter weather here is not so much about accumulating snow like in the mountains. It's more changeable conditions including black ice.

I did a lot of research and IMO the best winter tires for our weather conditions are the Michelin X-Ice SNOW. Early one morning right after I installed my winter tires, I got stuck in a traffic jam at a red light near my house. Black ice! Cars all around me just spinning their drive wheels unable to move. Guys were getting out and pushing each other off the road. Once the car in front of me was out of the way, I drove around them all like the pavement was dry! Then I went right to an empty iced parking lot to play. Amazing grip on the ice!

Note: if I lived in the mountains with unplowed snow and a lot of snowfall I may have gone with Blizzak WS90. They are noisy but supposed to handle gobs of unplowed snow the best.

Especially since you are RWD, I'd highly recommend going with a winter set of these tires in South Jersey. You can go with the stock size 225/45-18, or best handling size 245/40-18. I went with stock size because winter tire gurus told me that wider tires are not better in unplowed snow. They said that thinner tires have traction to cut through the snow while wider tires tend to hydroplane over it which is less control.

I actually try to buy my tires through Sam's Club if they can order what I want. Their prices are very reasonable (same or better than TireRack) and they provide lifetime service and rebalancing. If I pickup a nail they patch it and rebalance for free.

When Sam's can't get a particular tire, the TireRack warehouse is only a hour away in Delaware where I can pickup new tires with no sales tax, and there's even a pickup discount for TireRack not having to ship them.

MD Motorwerke in Somerdale NJ is an excellent independent shop to get maintenance done.

There are a lot of enthusiasts and events, hopefully again as Covid gets under control. Vaccinations are well organized and increasing briskly here. Mask wearing is pretty much a 100% compliance with the public. So hopefully that will mean more car events again.

Kies Motorsports is in South Jersey. They usually sponsor a big BMW charity car show around July every year. It will probably be the largest on the east coast when they can do it again.

Welcome to South Jersey!

[ctpolyak]

Thank you all for the input. Plenty to digest and time to make a decision before next winter!