[bmwnewbie22]

Hey guys, sorry if this is a redundant thread. I am finally a new owner of a 535i xdrive 2011 and new to this forum as well. The previous owner emphasized that I should replace tires. A local tire shop suggested 245/50R18 instead of the stock 245/45R18. I seek comments /suggestions from experts here. What impact does it have ride wise (smoother? more comfort?), technically to the car itself (I read somewhere the odometer is slightly off). Appreciate all the help. thanks.

[cdmulders]

Originally Posted by bmwnewbie22

A local tire shop suggested 245/50R18 instead of the stock 245/45R18. I seek comments /suggestions from experts here. What impact does it have ride wise (smoother? more comfort?), technically to the car itself (I read somewhere the odometer is slightly off). Appreciate all the help. thanks.

I ran this exact tire & wheel size for my winter setup for five seasons on my 535xi. No issues whatsoever. The ride was a little softer, and the speedometer actually provided the correct speed, given that my speedo with OEM tires/wheels padded the speed a bit, by about 3-4%.

[bmwnewbie22]

Thanks for the reply. I think I will go with the 50R18s and will update this thread with my experience.

[TEF]

According to a website calculator, by going from a 45 to 50 profile: "When speedometer reads 60 km/h actual speed will be 62.2 km/h". Additionally, your ride will be smoother and not much else changes.

Try this website for more details: https://www.wheel-size.com

[.BMW.]

I use 245/50-18 as winter tire setup, works great!

The speedo will actually be spot on with the taller tires. Since it reads high from factory.

[cdmulders]

Originally Posted by .BMW.

I use 245/50-18 as winter tire setup, works great!

The speedo will actually be spot on with the taller tires. Since it reads high from factory.

Indeed, this was my experience as well.

[bmwnewbie22]

Originally Posted by cdmulders

Indeed, this was my experience as well.

Thanks everyone. I'm planning to change mine this week. Looking forward to a more comfortable ride.

[TEF]

Based on this thread, it appears that many of us enjoy a smoother-riding car. However, the industry trend (including BMW) is to offer vehicles with with ever-increasing wheel sizes (i.e. 18>19>20) and lower and lower profile tires. This is even the case with SUVs. In some instances, customers are charged extra for these combinations. Recently, I noticed a new 2018 5 series with factory-optional 20" wheels and tires costing $5,000. As wheel sizes increase, the tire portion gets thinner and thinner, so what's the natural progression of this trend: painting the outer edge of an alloy wheel with black paint to simulate a tire? Add to this rock hard OE run flat tires and it's no wonder companies repairing bent rims are doing well.

[bmwnewbie22]

Agreed. I discovered an oscillating humming sound today . Posted another thread for this. Didnt get the tires yet Need to get to the core of this. The sound is quite annoying !!

[bmwnewbie22]

Originally Posted by bmwnewbie22

Agreed. I discovered an oscillating humming sound today . Posted another thread for this. Didnt get the tires yet Need to get to the core of this. The sound is quite annoying !!

So I showed it to a trustworthy mechanic. He drove it and didn't find anything unusual. Said that's how bmws feel like very unlike the super quiet mercs (he owns a x5). I will continue enjoying it and hopefully will get used to it. With traffic around the sound is less prominent. Will still go for the 50R18s for a quieter ride. Thanks for all the input folks.

[bmwnewbie22]

Just got the brand new Driveguards RFT and am very pleased. Ended up sticking to the 45R18s for now. I have to say, the car drives like new. The cabin noise disappeared. They dont feel like run flats at all. They do seem to take a side on pot holes but have to drive more to know more. Plus these are all season, so have to see how they perform in rain / snow. Will update more later.

[Riddleryan]

Hey, new owner of a 2011 BMW 535i xdrive like the maker of this thread and new to forum as well. Like his, mine came with the stock 245/45R18. I'll put 19"s on them some time in the future but for now, what do we think about running a 255/45R18?

I'm also sticking to a square setup until I go into changing the wheels.

Appreciate all answers!

[ezaircon4jc]

Originally Posted by Riddleryan

Hey, new owner of a 2011 BMW 535i xdrive like the maker of this thread and new to forum as well. Like his, mine came with the stock 245/45R18. I'll put 19"s on them some time in the future but for now, what do we think about running a 255/45R18?

I'm also sticking to a square setup until I go into changing the wheels.

Appreciate all answers!

Check here...

https://www.wheel-size.com/ or https://tiresize.com/calculator/

This will tell you what sizes you can use and stay as close to stock as possible. Ideally, you want to stay within 1% of stock.

[Riddleryan]

Originally Posted by ezaircon4jc

Check here...

https://www.wheel-size.com/ or https://tiresize.com/calculator/

This will tell you what sizes you can use and stay as close to stock as possible. Ideally, you want to stay within 1% of stock.

Thanks, brother!

I saw the www.wheel-size.com suggestions before. It made me believe it wasn't possible. But looking at your tiresize.com link, says it might be. +1.1% difference.




Think I need spacers for such a difference or no?

[ezaircon4jc]

Originally Posted by Riddleryan

Thanks, brother!

I saw the www.wheel-size.com suggestions before. It made me believe it wasn't possible. But looking at your tiresize.com link, says it might be. +1.1% difference.

Attachment 2276677


Think I need spacers for such a difference or no?

Spacers have nothing to do with tire/wheel size. They are for pushing the wheel further away from the hub. A 1.1% difference should be just fine. I think I was wrong initially and the difference should be less than 3%. That said, with X-Drive you'd want to be as close as possible to stock. Don't want to destroy the transfer case...

[cdmulders]

Originally Posted by Riddleryan

Thanks, brother!

I saw the www.wheel-size.com suggestions before. It made me believe it wasn't possible. But looking at your tiresize.com link, says it might be. +1.1% difference.
Think I need spacers for such a difference or no?

Riddleryan, I must admit that I'm not understanding what you are hoping to accomplish. As ezaircon4jc stated, there is no correlation between spacers and tire / wheel size per se, except for the location inboard or outboard of the wheel with respect to suspension and fenders.

If you are suggesting to go with a square setup (as you initially stated), then with four identical wheels and tires, your xDrive will not even notice the difference, so you can go to 255 vice 245 width tires (all around), since front and back will be the same. Having said that, I'm not sure what advantage you are anticipating by increasing the width of your tire tread by only 10mm (less than 1/2 inch). If you wish to change the ride and/or ability to absorb bumps, then you would need to change (and raise) the ratio of your tire, from the stock 45 to something like 50. I ran winter tires with 245/50/18 specs (on 18 inch wheels obviously) on my xDrive with no issues whatsoever. The car was not lowered, however.

What exactly are you intending to accomplish?

Cheers.

[Riddleryan]

Originally Posted by ezaircon4jc

Spacers have nothing to do with tire/wheel size. They are for pushing the wheel further away from the hub. A 1.1% difference should be just fine. I think I was wrong initially and the difference should be less than 3%. That said, with X-Drive you'd want to be as close as possible to stock. Don't want to destroy the transfer case...

I get it now. Thanks.

[Riddleryan]

Originally Posted by cdmulders

Riddleryan, I must admit that I'm not understanding what you are hoping to accomplish. As ezaircon4jc stated, there is no correlation between spacers and tire / wheel size per se, except for the location inboard or outboard of the wheel with respect to suspension and fenders.

If you are suggesting to go with a square setup (as you initially stated), then with four identical wheels and tires, your xDrive will not even notice the difference, so you can go to 255 vice 245 width tires (all around), since front and back will be the same. Having said that, I'm not sure what advantage you are anticipating by increasing the width of your tire tread by only 10mm (less than 1/2 inch). If you wish to change the ride and/or ability to absorb bumps, then you would need to change (and raise) the ratio of your tire, from the stock 45 to something like 50. I ran winter tires with 245/50/18 specs (on 18 inch wheels obviously) on my xDrive with no issues whatsoever. The car was not lowered, however.

What exactly are you intending to accomplish?

Cheers.

Ok, so big picture, I actually just wanted to get bigger tires (255/50) until I am ready for the bigger wheels as mentioned. I asked around and I got a bunch of mixed answers, all discouraging. A tire shop actually told me that I would need spacers. When I asked why, they said something about to avoid the bigger tires rubbing on the inner fender walls when I make the sharpest of turns (in the front, of course). So I would need spacers to push the tires out a little. I got confused and started doubting what I thought I knew but being as this is my first bimmer, I'm in love with it and don't wanna make mistakes. So in my head, I brought down the number to 255/45.

But then I thought.....why not ask people who actually drive bimmers and know this stuff in and out?

So here I am.

Just want to hear from people more knowledgeable in this stuff than I or the people I talked to are (none of them owned bimmers, btw)

[cdmulders]

OK. That makes sense. You can certainly run 245/50/18 tires without spacers on OEM wheels. 255/50/18 would only be wider by 5mm on each side (all other things being equal) so the chances of your tires rubbing either the suspension or the fender well are minimal with OEM wheels. Having said that, I tried a 15mm spacer on my 245/50/18 tire/wheel combo in the front, and it was a disaster. The tire did make contact with the fender (with the spacer).

Back to your intent to make your tires larger (larger overall diameter which is what you do by going to a 50 tire), I don't get the connection yet between that and you getting ready for larger diameter wheels. When you get the larger wheels, you then put on tires that keep the same overall diameter as before, which with our F10s usually works out to be one ratio lower per extra inch of wheel. That's why you get 245/45/18, 245/40/19, and 245/35/20 tire sizes for front wheels, and where the rears are staggered, you get 275/40/18, 275/35/19 and 275/30/20 tires. The staggered sizes also keep the tire diameter between front and back within 1%. People that don't have xDrives do have more flexibility with staggered setups, and some go as wide as 295 on the rears (and I've seen one person mention they were running 305s).

I'm starting to ramble on, so I'll stop here. Your plan to go with 255/45/18 or even 255/50/18 should be OK if you are using regular F10 18" wheels. If you do decide on 255 tires, I'd check on the width of the wheel. If they are 8.5", you are OK. If they are only 8", you might be putting on a tire that looks too wide (it will bulge out to the tread).

[Riddleryan]

Originally Posted by cdmulders

OK. That makes sense. You can certainly run 245/50/18 tires without spacers on OEM wheels. 255/50/18 would only be wider by 5mm on each side (all other things being equal) so the chances of your tires rubbing either the suspension or the fender well are minimal with OEM wheels. Having said that, I tried a 15mm spacer on my 245/50/18 tire/wheel combo in the front, and it was a disaster. The tire did make contact with the fender (with the spacer).

Back to your intent to make your tires larger (larger overall diameter which is what you do by going to a 50 tire), I don't get the connection yet between that and you getting ready for larger diameter wheels. When you get the larger wheels, you then put on tires that keep the same overall diameter as before, which with our F10s usually works out to be one ratio lower per extra inch of wheel. That's why you get 245/45/18, 245/40/19, and 245/35/20 tire sizes for front wheels, and where the rears are staggered, you get 275/40/18, 275/35/19 and 275/30/20 tires. The staggered sizes also keep the tire diameter between front and back within 1%. People that don't have xDrives do have more flexibility with staggered setups, and some go as wide as 295 on the rears (and I've seen one person mention they were running 305s).

I'm starting to ramble on, so I'll stop here. Your plan to go with 255/45/18 or even 255/50/18 should be OK if you are using regular F10 18" wheels. If you do decide on 255 tires, I'd check on the width of the wheel. If they are 8.5", you are OK. If they are only 8", you might be putting on a tire that looks too wide (it will bulge out to the tread).

Thanks, cdmulders!

Makes perfect sense.


See...I knew there was a reason I came here.