Common rub points and how to address them

drwankel · 05-22-2022, 07:13 PM

I've recently had a chance to view a bunch of different modded e9x m3's and there was one thing that jumped out at me: Every single car seems to be rubbing in the exact same 3 places despite the wide variety of suspension/wheel/tire setups.

In this thread- we'll talk about each of those rub spots, and how to address them.

Front Wheels :

1. Scrubbing the rear of the fender liner.

This rub will be nearly identical on both sides. There is hard metal behind this spot, so massaging the fender liner is not possible. The fixes need to come from the wheel/tire setup, and will be either one of the below or a combination of the fixes below:

Increase wheel offset, either by changing wheels, or removing spacers. Adding spacers WILL make this worse.
Run shorter tires
Run narrower tires- which in turn will be shorter as well due to aspect ratio

2. Rub on the bulge on the rear of the right fender liner:

This rub only occurs on the right side of the car. The bulge is not present on the left side. Behind this bulge is the windshield wiper fluid reservoir. There is likely a small amount of manipulation you can do with the fender liner to add clearance either with a heat gun or trimming here. Fixes are the same for the above:

Increase wheel offset, either by changing wheels, or removing spacers. Adding spacers WILL make this worse.
Run shorter tires
Run narrower tires- which in turn will be shorter as well due to aspect ratio

Rear Wheels

1. Rubbing on the fender liner bulge where the fender meets the bumper:

A few things to note. This nub protrudes more on the left side of the car than the right side and this is NORMAL. Every single car I checked was like this. This also means you may only notice rub on the left side tire and not the right side. Fixes are simple:

Shave off the nub

Observed a ton of cars taking this mitigation successfully. Seems to be more common than I thought.

Final thoughts and warnings:

It's quite odd that the same 3 spots seem to impact most cars. I had assumed that different wheel/tire/suspension setups would have had slightly different rub locations, but that just doesn't seem to be the case

Lastly- BEWARE THE PS4S tire! The PS4S tire has very square/wide shoulders which can cause rubbing when other tire models don't rub at all. So when someone says this wheel/tire/suspension setup doesn't rub, pay extra attention to what tire model they are running.

I'm sure there are other less common rub spots out there- but these are the run away common ones. Hopefully this information helps someone in the future.

Scrippy · 05-22-2022, 08:09 PM

I'm lowered and have them all. They worked themselves out without issue. Lol it actually looks like I proactively did something like neat dremel trimming

drwankel · 05-22-2022, 08:25 PM

It's quite odd how ride height seemed to have very little to do with it. Symptoms were the same accross cars that were stock height or lowered. The common thread was wider wheels/tires, running spacers, or a combination of both.

In my car, at some point I had hit all 3 of these, and my car isnt lowered, but is a factory ZCP car there is a slight ride height drop.

nycplumber · 05-22-2022, 09:23 PM

Good info but at the same time I think if most people could see my fender liners they wouldn't give a damn about rubbing. Mine are beat up pretty damn bad but work just fine.

drwankel · 05-22-2022, 10:06 PM

Quote:

Originally Posted by nycplumber

Good info but at the same time I think if most people could see my fender liners they wouldn't give a damn about rubbing. Mine are beat up pretty damn bad but work just fine.

There is some truth to this. Some of the cars I looked at, the owners had taken the approach of let it rub, and the result wasn't as bad as I was expecting. Nobody had giant holes or anything of the like in their liners. Some were paper thin in places. The liner was still functional.

//steve\\ · 05-23-2022, 06:08 AM

Quote:

Originally Posted by Scrippy

I'm lowered and have them all. They worked themselves out without issue. Lol it actually looks like I proactively did something like neat dremel trimming

Pretty much my exact take on it Mine all show signs of rubbing and the fronts are totally worn through up front. Doesn't seem like you can avoid it if you're actually really driving the car hard.

SilverSlug · 06-10-2022, 04:55 AM

When you say "right side" or "left side" do you mean drivers side or passengers side?

DrFerry · 06-10-2022, 07:28 AM

Sub'd, because the hive mind might have a few other solutions up its sleeve... Totally agree that smaller diameter tires - i.e. tires with diameters smaller than the original equipment sizes - fixes the rubbing issue. The Brand of tire can also fix it - due to tire shoulder shape (mold shape). But not all tires labelled with the exact same size have the same outer diameter(s) due to the T&RA / ETRTO / JATMA dimensional design "windows" chosen by their manufacturers. Hence, smaller O.D. is definitely better to fix rubbing. But how small is 'smaller' and enough? About 0.3 to 0.4 inches on the overall diameter in my experience. I tend to think that alignment also plays a role when combined with a different tire shape. Perhaps caster being the main contributing factor. Though that's only my speculation as I have no data to back that feeling up other than to say with increased castor most vehicles gain positive camber when turning the wheels (either dynamically or statically).
.

SilverSlug · 06-10-2022, 10:58 AM

I didn't even know it was possible to adjust castor?

However this leads me to realize that perhaps just doing an alignment (especially after adding spacers or upsizing tires), may help with toe angles, and perhaps subsequently reduce a rubbing location.

DRLane · 06-10-2022, 12:30 PM

Quote:

Originally Posted by SilverSlug

I didn't even know it was possible to adjust castor?

However this leads makes me realize that perhaps just doing an alignment (especially after adding spacers or upsizing tires), may help with toe angles, and perhaps subsequently reduce a rubbing location.

Need either race camber plates (with adjustable caster) or adjustable length thrust arms. One pulls from the top, other pulls/pushes from the bottom. I don't think you can adjust caster with OEM suspension components.

drwankel · 06-10-2022, 03:19 PM

Quote:

Originally Posted by DRLane

Need either race camber plates (with adjustable caster) or adjustable length thrust arms. One pulls from the top, other pulls/pushes from the bottom. I don't think you can adjust caster with OEM suspension components.

Correct, the only adjustment in the front when stock is Toe. You can get a small amount of extra camber by pulling the alignment pins, but that's it. No caster adjustment.

Z K · 06-13-2022, 03:24 PM

For the rear rubbing where the bumper meets the fender. The design is different on the sedan vs the coupe. The sedan will not only rub on the fender liner, it will also rub on the hard plastic piece right behind it. I see many people shave down the hard plastic. The coupe does not seem to have this issue.

alpine2530 · 09-11-2022, 12:36 PM

This has been very frustrating for me. Recently purchased a squared 18x10.5 et22 setup and there’s a fair bit of rubbing in the front as shown in the pictures.

I’m tempted to ignore and continue driving this way till it has worn itself off. Although, how safe is it? Any solid advise?

drwankel · 09-12-2022, 11:59 AM

Quote:

Originally Posted by alpine2530

This has been very frustrating for me. Recently purchased a squared 18x10.5 et22 setup and there’s a fair bit of rubbing in the front as shown in the pictures.

I’m tempted to ignore and continue driving this way till it has worn itself off. Although, how safe is it? Any solid advise?

That does not seem like a good setup for the front honestly. Too wide, and to little offset. The risk of rubbing on the front like that is that if your setup is extreme enough like the one you listed, once you rub through the fender liner, you'll start polishing the frame next, which I'm sure will do wonderful things to the tires. There's no extra space behind those rub points in the front liner.

Best option unfortunately is to move to a different wheel setup, or just live with the rubbing.

alpine2530 · 09-12-2022, 11:42 PM

Quote:

Originally Posted by drwankel

That does not seem like a good setup for the front honestly. Too wide, and to little offset. The risk of rubbing on the front like that is that if your setup is extreme enough like the one you listed, once you rub through the fender liner, you'll start polishing the frame next, which I'm sure will do wonderful things to the tires. There's no extra space behind those rub points in the front liner.

Best option unfortunately is to move to a different wheel setup, or just live with the rubbing.

You mean different tyre setup? Will 295/30r18 clear up front? I could live with slight rub at full lock.

spammysammich · 09-12-2022, 11:59 PM

You need a narrower rim and tire to not rub at all. I'm running 18x9.5 et22 up front and 265/35/18 rub at around mid turn in both Continental DWS 06+ and PS4S. Full lock clears the mid-liner bump that is a common point of contact as shown above.

drwankel · 09-14-2022, 12:39 AM

Quote:

Originally Posted by alpine2530

You mean different tyre setup? Will 295/30r18 clear up front? I could live with slight rub at full lock.

A 10.5" +22 wheel going to rub no matter what tire you put on it in the front. It's too wide, and that offset will cause it to poke past the fenders as well, which makes the rubbing even worse.

A 295/30/18 tire will rub in the front no matter what wheel you are running. Simply too wide.

Adam M · 12-21-2022, 09:17 AM

Does anyone have any data on the relative sizes of different brands.

I’ve read so many times, 275 30 19 ok a square set up, will not run, even with MP4S, but that doesn’t seem to be the case across the board.

I’m inclined to leave the MP4S behind and get contisport7 because if the reviews but am concerned about making the situation worse.

05-22-2022, 07:13 PM	#1
drwankel Major 1032 Rep 1,041 Posts Drives: 2012 E92 M3 ZCP, 2021 M340i Join Date: Feb 2016 Location: Bothell, WA iTrader: (0)	Common rub points and how to address them I've recently had a chance to view a bunch of different modded e9x m3's and there was one thing that jumped out at me: Every single car seems to be rubbing in the exact same 3 places despite the wide variety of suspension/wheel/tire setups. In this thread- we'll talk about each of those rub spots, and how to address them. Front Wheels : 1. Scrubbing the rear of the fender liner. This rub will be nearly identical on both sides. There is hard metal behind this spot, so massaging the fender liner is not possible. The fixes need to come from the wheel/tire setup, and will be either one of the below or a combination of the fixes below: Increase wheel offset, either by changing wheels, or removing spacers. Adding spacers WILL make this worse. Run shorter tires Run narrower tires- which in turn will be shorter as well due to aspect ratio 2. Rub on the bulge on the rear of the right fender liner: This rub only occurs on the right side of the car. The bulge is not present on the left side. Behind this bulge is the windshield wiper fluid reservoir. There is likely a small amount of manipulation you can do with the fender liner to add clearance either with a heat gun or trimming here. Fixes are the same for the above: Increase wheel offset, either by changing wheels, or removing spacers. Adding spacers WILL make this worse. Run shorter tires Run narrower tires- which in turn will be shorter as well due to aspect ratio Rear Wheels 1. Rubbing on the fender liner bulge where the fender meets the bumper: A few things to note. This nub protrudes more on the left side of the car than the right side and this is NORMAL. Every single car I checked was like this. This also means you may only notice rub on the left side tire and not the right side. Fixes are simple: Shave off the nub Observed a ton of cars taking this mitigation successfully. Seems to be more common than I thought. Final thoughts and warnings: It's quite odd that the same 3 spots seem to impact most cars. I had assumed that different wheel/tire/suspension setups would have had slightly different rub locations, but that just doesn't seem to be the case Lastly- BEWARE THE PS4S tire! The PS4S tire has very square/wide shoulders which can cause rubbing when other tire models don't rub at all. So when someone says this wheel/tire/suspension setup doesn't rub, pay extra attention to what tire model they are running. I'm sure there are other less common rub spots out there- but these are the run away common ones. Hopefully this information helps someone in the future. Attached Images Last edited by drwankel; 05-22-2022 at 10:15 PM..
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05-22-2022, 08:09 PM	#2
Scrippy Lord Scrip 1812 Rep 3,012 Posts Drives: 2011 M3 Coupe Join Date: Jan 2012 Location: LA,Ca iTrader: (0) Garage List [0.00] 2007 BMW 335i [0.00]	I'm lowered and have them all. They worked themselves out without issue. Lol it actually looks like I proactively did something like neat dremel trimming __________________
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05-22-2022, 08:25 PM	#3
drwankel Major 1032 Rep 1,041 Posts Drives: 2012 E92 M3 ZCP, 2021 M340i Join Date: Feb 2016 Location: Bothell, WA iTrader: (0)	It's quite odd how ride height seemed to have very little to do with it. Symptoms were the same accross cars that were stock height or lowered. The common thread was wider wheels/tires, running spacers, or a combination of both. In my car, at some point I had hit all 3 of these, and my car isnt lowered, but is a factory ZCP car there is a slight ride height drop.
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05-22-2022, 09:23 PM	#4
nycplumber Major 682 Rep 1,226 Posts Drives: slow Join Date: Apr 2016 Location: nyc iTrader: (0)	Good info but at the same time I think if most people could see my fender liners they wouldn't give a damn about rubbing. Mine are beat up pretty damn bad but work just fine.
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06-10-2022, 04:55 AM	#7
SilverSlug Hey, where have you been all my life? 680 Rep 1,401 Posts Drives: 2011 M3 6MT Join Date: Jul 2018 Location: San Francisco, CA iTrader: (2)	When you say "right side" or "left side" do you mean drivers side or passengers side?
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06-10-2022, 07:28 AM	#8
DrFerry Field Marshal 6727 Rep 1,829 Posts Drives: '08 E92 M3 Join Date: Jul 2010 Location: Greenville, SC iTrader: (5) Garage List 2008 BMW M3 [5.25] 2015 BMW X5 [4.50]	Sub'd, because the hive mind might have a few other solutions up its sleeve... Totally agree that smaller diameter tires - i.e. tires with diameters smaller than the original equipment sizes - fixes the rubbing issue. The Brand of tire can also fix it - due to tire shoulder shape (mold shape). But not all tires labelled with the exact same size have the same outer diameter(s) due to the T&RA / ETRTO / JATMA dimensional design "windows" chosen by their manufacturers. Hence, smaller O.D. is definitely better to fix rubbing. But how small is 'smaller' and enough? About 0.3 to 0.4 inches on the overall diameter in my experience. I tend to think that alignment also plays a role when combined with a different tire shape. Perhaps caster being the main contributing factor. Though that's only my speculation as I have no data to back that feeling up other than to say with increased castor most vehicles gain positive camber when turning the wheels (either dynamically or statically). . __________________ '08 E92 M3 DCT Melbourne Red/Bamboo Beige Leather/EDC/SSP Spec-R DCT clutch discs/SSP Pro-Gold DCT Fluid/Quaife LSD/3:45 Final Drive by Diffs Online/BE Bearings & ARP Bolts/Vibra Technics Engine Mounts/M3 World HFC X-Pipe/LUX H8 180/BPM Sport DCT Tune/PFC Z-Rated Pads/ECS Brass Brake Caliper Bushings/Alex Shop Solid Sub-frame Bushings/Motul 600/Tint Last edited by DrFerry; 06-10-2022 at 07:40 AM..
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06-10-2022, 10:58 AM	#9
SilverSlug Hey, where have you been all my life? 680 Rep 1,401 Posts Drives: 2011 M3 6MT Join Date: Jul 2018 Location: San Francisco, CA iTrader: (2)	I didn't even know it was possible to adjust castor? However this leads me to realize that perhaps just doing an alignment (especially after adding spacers or upsizing tires), may help with toe angles, and perhaps subsequently reduce a rubbing location.
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06-13-2022, 03:24 PM	#12
Z K Major General 1887 Rep 5,506 Posts Drives: E90 M3, G20 M340i Join Date: Jul 2011 Location: San Francisco iTrader: (3)	For the rear rubbing where the bumper meets the fender. The design is different on the sedan vs the coupe. The sedan will not only rub on the fender liner, it will also rub on the hard plastic piece right behind it. I see many people shave down the hard plastic. The coupe does not seem to have this issue. Attached Images __________________ Auto Detailing Enthusiast!
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09-11-2022, 12:36 PM	#13
alpine2530 Enlisted Member 10 Rep 36 Posts Drives: E92 M3 Join Date: Mar 2021 Location: UAE iTrader: (0)	This has been very frustrating for me. Recently purchased a squared 18x10.5 et22 setup and there’s a fair bit of rubbing in the front as shown in the pictures. I’m tempted to ignore and continue driving this way till it has worn itself off. Although, how safe is it? Any solid advise?
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09-12-2022, 11:59 PM	#16
spammysammich Major 1579 Rep 1,099 Posts Drives: 2009 E92 M3 Dakar Yellow II Join Date: Oct 2021 Location: Edmonds, WA iTrader: (0) Garage List 2009 BMW M3 [10.00]	You need a narrower rim and tire to not rub at all. I'm running 18x9.5 et22 up front and 265/35/18 rub at around mid turn in both Continental DWS 06+ and PS4S. Full lock clears the mid-liner bump that is a common point of contact as shown above.
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12-21-2022, 09:17 AM	#18
Adam M Private First Class 67 Rep 114 Posts Drives: BMW e92 M3 Join Date: Sep 2022 Location: London iTrader: (0)	Does anyone have any data on the relative sizes of different brands. I’ve read so many times, 275 30 19 ok a square set up, will not run, even with MP4S, but that doesn’t seem to be the case across the board. I’m inclined to leave the MP4S behind and get contisport7 because if the reviews but am concerned about making the situation worse.
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