530e60

Hi there,

Having just installed 20 inch wheels with 255/35 R20 tires, I am experiencing some problems. Mostly during turning, it appears that the front wheels are touching the arch plastic moulding (i.e. if you look inside the wheels well, there is a plastic moulding in front of the wheels or behind the sides of the front bumper).

Is it the wrong wheel/tire size? Any wheel experts can suggest any remedies?

I read on some web site that some modification may be required when installing 20 inch wheels? Anyone know what modifications and how to do it?

Looking forward to hearing from all asap.

Thanks

cidair

Have you altered the offset?

255/35-20 seems like a little too big diameter to fit.

Will check my wheel size table and get bak ( when i find it ).

I have 245/35-19 in front and ET 10 ( means a little wider than standard ).

It works find except when cornering hard and hitting a bump on the outside wheel.
The I can hear the tyre briefly rubbing against the plastic insside the wheel well.

cidair

Your 255/35-20 has a outer diameter of 686mm.

My 245/35-19 has 655mm.

The OEM 18" 245/40-18 has 653mm.

The 686mm and offset can very well be the problem. Especially when you go to the extreme angles with the steering.

I choose the 19" because I was able to get a combination with tyres that would be as close as possible to the standard wheels.

530e60

I too had the original 245/40 R18 run flat. I didnt quite follow the math on the larger wheel diameter. How is it calculated?

Based on your calulation, can you please advise which tire size is more appropriate for the 20s? 255/30? 255/25?

Since the vehicle has been barely driven 20 miles since installation yesterday, I can go back today to check if they can exchange them.

Thanks for your quick replies. I really need em.

530e60

cidair,

No offset altered. by offset i presume you mean whether a spacer or washer was put in along with the wheels whereby the wheel would stick out a bit more on the sides. they didnt really put anything like that (i think perhaps because the width of the wheels is only 8.5)

Do you think it is needed? Should I ask them to put offset? Any offset size recommendations?

cidair

I just looked in my wheel size table. It states all diameters and rolling circumferences of all " normal " tyre sizes.

You probaly have to go for 30-profile or maybe even 25-profile to get down to acceptable diameter.

But it could also be the offset. Ask your wheels supplier what offset you have.
I don?t remember the OEM offset on the front wheels ( somewhere around ET20-22 I think ). So if you, like me have a lesser offset ( ET10 on mine ) your wheels will be further out in the wheel wells, causing the rubbing. On the other hand, if you have too much offset they would probably rub on the inner part of the wheel wells.

Follow?

I think you should go back to the tyre company and sort it out. Could be dangerous if you drive fast in a corner and hit a bump. Suspension bottoms out and tyre rubs / brakes towards inner wheel well - understeer and off you go!

tubbee

Hi cidair,

I was thinking of installing 245/35/19 for my front rims as well and I am a little concerned about rubbing, especially after I lower my car. Is your car lowered?

What are you running on the back , I am going for 275/30/19.

Thanks for your advice.

Tubbs

cidair

I have the OEM sports suspension and run 275/30-19 at rear.

It?s a very good setup I think.

Bunbun

Hi

I checked online with www.tires.com seems like the correct tire size for your 20" wheel should be 255/30-20. Maybe the extra "5" causes it to touch.

Hope it helps

Bunbun

herb

530e60 what's the size of your front wheels? recomended tire up front are 255-30-20 .. what brand are your wheelsand is the car lowered? im running 20x9 with 245-35-20 & lowered and i dont have rubbing probem.. it also depends on what wheel offset you have..