[drewfromthehou]

I live in Houston and just purchased my first BMW a 2020 X3 M40i with the 21 inch wheels. While I was having it detailed today the detail guy told me while the wheels are beautiful, they were a really bad decision for Houston. He said they would put me at risk during our frequent flooding events if I had to go through water. I had never heard this before, part of me thinks he had no idea what he was talking about but thought I would jump on the forum with it. Anyone have experience driving these cars in flooded roadways? How did it do?

[MikesBMW]

How would wheel size affect a cars risk of getting flooded in high water? I don't get it.. your less at risk of being flooded vs an X1 and more at risk vs an X5. Ground clearance is probably all that matters

[drewfromthehou]

Originally Posted by BMW135iMike

How would wheel size affect a cars risk of getting flooded in high water? I don't get it.. your less at risk of being flooded vs an X1 and more at risk vs an X5. Ground clearance is probably all that matters

Yeah I don't get it either. I agree it has nothing to do with the ground clearance but he was insinuating that the wheels would cause the vehicle to be swept away easier than smaller wheels. Which in theory just doesn't add up to me.

I am sure he was just talking to be talking...

[SteveX3M40i]

Hi,
I think he should stick to detailing - rather than becoming a physics teacher!
Cheers
Steve

[GT500R]

Risk as in 21” are harder to handle with flooding and going through puddles? Lol

[X3BimmerX3]

I have lived in Houston for 50 years and many floods. Don’t drive in high water, period. Those that do are stupid. The news always tells you not to do it and shows what happens to the idiots that do, including drowning to death.

[london_v]

Originally Posted by SteveX3M40i

Hi,
I think he should stick to detailing - rather than becoming a physics teacher!
Cheers
Steve

Perfectly said.

[atrueb]

Maybe he is referring to aquaplaning? Not sure, but my understanding is that the tread on 21" tires is probably less deep than on 19". And the staggered 21" may be more prone to aquaplaning with the 275 rear tires compared to the square 19" setup with 245 all round.

[Bristle Hound]

Originally Posted by SteveX3M40i

Hi,
I think he should stick to detailing - rather than becoming a physics teacher!
Cheers
Steve

This ^
Sounds BS to me TBH

[Sportstick]

I suspect some poor communication changed the detail guy's intention. 21" wheels often come with wide tread width tires. Just as on snow, a wide tread width will start to "surf" over rushing water more easily and at a lower speed, resulting in loss of control more quickly than narrower tires. If tread widths on your 21s are the same as, for example, 18s, then I would not see a difference beyond shorter-sidewall damage from potholes/broken concrete that the floods might create.

[drewfromthehou]

Cool, yeah I thought it was total BS too. I don't expect to have to drive through high water but was taken off guard by the comment. Now that it seems most everybody is one the same page, I am not going to worry about it.

[Sportstick]

Originally Posted by drewfromthehou

Cool, yeah I thought it was total BS too. I don't expect to have to drive through high water but was taken off guard by the comment. Now that it seems most everybody is one the same page, I am not going to worry about it.

Perhaps not total....with wider tires, I would keep speeds lower than otherwise on any measureable water. Don't worry, but take reasonable precautions.

[Aliendrive]

I was waiting for the PSA don't drown turn around