[Dark Star]

Hi folks,

I picked up a used 2013 335i xDrive recently which is having some vibration issues when driving and braking which I think is linked to the tires/wheels that it came with. I tried to research this on my own but had difficulty figuring it out so sorry if this has been answered before.

The car has 225/45/18 in front on 18x8 wheels with 245/45/18 on 18x8.5 in the back. The mechanic that checked the car out for me stated that the vibration issues are likely due to the staggered set up and he warned that the transfer case would be damaged in time with this set up. So here are my questions...

1. Is this set up indeed a risk for the xDrive transfer case? This is my first time using this mechanic so just want to double check.
2. Can I fit 225/45/18 on the 18x8.5 in the back without too much stretching?

Thanks in advance for helping get this ride running smooth.

[DJSF3014]

Originally Posted by Dark Star

Hi folks,

I picked up a used 2013 335i xDrive recently which is having some vibration issues when driving and braking which I think is linked to the tires/wheels that it came with. I tried to research this on my own but had difficulty figuring it out so sorry if this has been answered before.

The car has 225/45/18 in front on 18x8 wheels with 245/45/18 on 18x8.5 in the back. The mechanic that checked the car out for me stated that the vibration issues are likely due to the staggered set up and he warned that the transfer case would be damaged in time with this set up. So here are my questions...

1. Is this set up indeed a risk for the xDrive transfer case? This is my first time using this mechanic so just want to double check.
2. Can I fit 225/45/18 on the 18x8.5 in the back without too much stretching?

Thanks in advance for helping get this ride running smooth.

Yes that is to much off should be 245/40 I believe. But I don't know if transfer case would cause vibration while braking most likely would be warped rotors if it's while braking. I'm pretty sure 225 would fit on 8.5 easy.

[shiftdnb]

yeah, that's not a good ratio at all. You want to be within 1%.

[Dark Star]

Originally Posted by DJSF3014

Yes that is to much off should be 245/40 I believe. But I don't know if transfer case would cause vibration while braking most likely would be warped rotors if it's while braking. I'm pretty sure 225 would fit on 8.5 easy.

Yeah the rotors, bushings, bearings, etc were checked and looked fine so mechanic recommend to start off by getting correct tire sizes on before I do anything else since a failed transfer case is gonna be a bigger issue than some vibrations. I don't think the transfer case is causing the vibrations, but I'm sure having the wrong sizes/ratio could be screwing up the car in general.

[Dark Star]

Originally Posted by shiftdnb

yeah, that's not a good ratio at all. You want to be within 1%.

Yeah that's what I hear. I suck at math and was just having difficulty figuring our what my ratio is. Looks like I'll be throwing some new tires on the rear soon.

[alohasurftoad]

255/40/18 is oem size for rear.

I wouldn't change it soon, id change it immediately

[Dark Star]

Originally Posted by alohasurftoad

255/40/18 is oem size for rear.

I wouldn't change it soon, id change it immediately

Oh no 225/45/18 square setup is OEM for the 2013 335i xDrive sedan. Its on the doorjamb. I do have an appointment with Les Schwab to swap them on Saturday though!

[chowser51]

He’s saying your rear for staggered should be 255/40/18.

So the 245/45/18 is throwing it off by almost an inch.

The 225/45 is 26” tall. The 255/40 is 26” tall. Good match.
The 245/45 is 26.7” tall.

So replace your rears with 255/40 to match OEM staggered sizes.

[shiftdnb]

Originally Posted by Dark Star

Yeah that's what I hear. I suck at math and was just having difficulty figuring our what my ratio is. Looks like I'll be throwing some new tires on the rear soon.

The immediate warning is that sidewall percentage number (2nd number) was the same for both tires. Which means that a wider tire is going to have a higher sidewall at the same percentage, which would make yours a huge difference.

[alohasurftoad]

Originally Posted by Dark Star

Oh no 225/45/18 square setup is OEM for the 2013 335i xDrive sedan. Its on the doorjamb. I do have an appointment with Les Schwab to swap them on Saturday though!

18" OEM wheels and tires may come in square or staggered on both RWD and X-drive. 18x8 ET34 with 225/45/18(26") square, or the staggered setup which is 18x8 ET34 225/45/18 front & 18x8.5 ET47 255/40/18(26") rear.

not sure how long this has been occurring, but hopefully your transfer case makes it to saturday.