Tire Size

JDAURIA · 01-02-2021, 06:00 PM

I have style 214 wheels with factory 275/40/20 and 315/35/20 tires.

I was wondering if I could get away with same front spec tires (275/40/20) but 305/40/20 in rear?

Long story short: I need new winter rear tires, the 35d decided to eat the current Pirelli Ice & Snow tires and last I checked TireRack was out of stock on them. Discount Tire and eBay have them for $490/each! Welp....

Weighing my options here. I could go with the new Vredestein Wintrac Pro tires, which are significantly cheaper than the Pirelli's and they are in stock. OR have to buy a dedicated winter setup now - something along the lines of style 335 (19s with 255/50/19 all around) or even style 209 (18s with 255/50/18 all around)

Thecastle · 01-03-2021, 09:57 AM

You 35d is awd correct? So going to the higher sidewall rears will increase the overall diameter of the tire reducing the rotating speed aka rpms per mph. This will cause a rotation speed mismatch between the front and rear axle. Could be a problem for the xfer case as it maybe detected as slip between front and rear. Can’t say if this is in tolerance for the xfer case. Would not recommend finding out. Make sure all tires are pretty close in rpms to avoid problems. Also generally recommend matched tires in awd vehicles.

JDAURIA · 01-03-2021, 11:14 AM

Yeah that was my concern :/

Hoping a tire expert could chime in.

Could I increase the front sidewall from 40 to 45 (275/45/20) and 305/40/20

Nyc Dito · 01-03-2021, 11:29 AM

Quote:

Originally Posted by JDNY516

Yeah that was my concern :/

Hoping a tire expert could chime in.

Could I increase the front sidewall from 40 to 45 (275/45/20) and 305/40/20

according to tire size dot com, that combo would put the fronts at 29.7" compared to the rears at 29.6" (in height).

JDAURIA · 01-03-2021, 05:03 PM

I probably won't risk it. I'll have to bite the bullet and buy new rears or source another set of winter tires

JDAURIA · 01-04-2021, 07:06 PM

Mods please close. I ended up buying a new set of Nokia R3's

01-02-2021, 06:00 PM	#1
JDAURIA Lieutenant Colonel 725 Rep 1,716 Posts Drives: F31 MSport Join Date: Jun 2008 Location: West Palm Beach, FL iTrader: (6) Garage List 2005 BMW [0.00] 2016 BMW [0.00]	Tire Size - 2nd opinion I have style 214 wheels with factory 275/40/20 and 315/35/20 tires. I was wondering if I could get away with same front spec tires (275/40/20) but 305/40/20 in rear? Long story short: I need new winter rear tires, the 35d decided to eat the current Pirelli Ice & Snow tires and last I checked TireRack was out of stock on them. Discount Tire and eBay have them for $490/each! Welp.... Weighing my options here. I could go with the new Vredestein Wintrac Pro tires, which are significantly cheaper than the Pirelli's and they are in stock. OR have to buy a dedicated winter setup now - something along the lines of style 335 (19s with 255/50/19 all around) or even style 209 (18s with 255/50/18 all around) __________________ 2016 F31 328iX \| Alpine White \| Black \| ///MSport \| iND \| Eventuri \| AC Schnitzer \| MPerformance \| 513M \| Michelin PS4 \| 2005 \| 330CiC \| Sparkling Graphite \| Black \| 6MT \| ZHP Purchase your W///AGON Stickers Here: https://f30.bimmerpost.com/forums/sh....php?t=1930190
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01-03-2021, 09:57 AM	#2
Thecastle Major 307 Rep 1,146 Posts Drives: F10 550i Join Date: Apr 2015 Location: Houston, TX iTrader: (0) Garage List 2020 BMW M340i [0.00] 2019 RAM 3500 [0.00] 2020 BMW X3 [0.00] 2016 BMW 550i [0.00] 2000 Ford F450 7.3l ... [0.00]	You 35d is awd correct? So going to the higher sidewall rears will increase the overall diameter of the tire reducing the rotating speed aka rpms per mph. This will cause a rotation speed mismatch between the front and rear axle. Could be a problem for the xfer case as it maybe detected as slip between front and rear. Can’t say if this is in tolerance for the xfer case. Would not recommend finding out. Make sure all tires are pretty close in rpms to avoid problems. Also generally recommend matched tires in awd vehicles.
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01-03-2021, 11:14 AM	#3
JDAURIA Lieutenant Colonel 725 Rep 1,716 Posts Drives: F31 MSport Join Date: Jun 2008 Location: West Palm Beach, FL iTrader: (6) Garage List 2005 BMW [0.00] 2016 BMW [0.00]	Yeah that was my concern :/ Hoping a tire expert could chime in. Could I increase the front sidewall from 40 to 45 (275/45/20) and 305/40/20 __________________ 2016 F31 328iX \| Alpine White \| Black \| ///MSport \| iND \| Eventuri \| AC Schnitzer \| MPerformance \| 513M \| Michelin PS4 \| 2005 \| 330CiC \| Sparkling Graphite \| Black \| 6MT \| ZHP Purchase your W///AGON Stickers Here: https://f30.bimmerpost.com/forums/sh....php?t=1930190
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01-03-2021, 05:03 PM	#5
JDAURIA Lieutenant Colonel 725 Rep 1,716 Posts Drives: F31 MSport Join Date: Jun 2008 Location: West Palm Beach, FL iTrader: (6) Garage List 2005 BMW [0.00] 2016 BMW [0.00]	I probably won't risk it. I'll have to bite the bullet and buy new rears or source another set of winter tires __________________ 2016 F31 328iX \| Alpine White \| Black \| ///MSport \| iND \| Eventuri \| AC Schnitzer \| MPerformance \| 513M \| Michelin PS4 \| 2005 \| 330CiC \| Sparkling Graphite \| Black \| 6MT \| ZHP Purchase your W///AGON Stickers Here: https://f30.bimmerpost.com/forums/sh....php?t=1930190
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01-04-2021, 07:06 PM	#6
JDAURIA Lieutenant Colonel 725 Rep 1,716 Posts Drives: F31 MSport Join Date: Jun 2008 Location: West Palm Beach, FL iTrader: (6) Garage List 2005 BMW [0.00] 2016 BMW [0.00]	Mods please close. I ended up buying a new set of Nokia R3's __________________ 2016 F31 328iX \| Alpine White \| Black \| ///MSport \| iND \| Eventuri \| AC Schnitzer \| MPerformance \| 513M \| Michelin PS4 \| 2005 \| 330CiC \| Sparkling Graphite \| Black \| 6MT \| ZHP Purchase your W///AGON Stickers Here: https://f30.bimmerpost.com/forums/sh....php?t=1930190
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