Questns abt handling of 325xi AFTER tire rotation etc.

[Feu]

I needed a new front tire for my BMW 325xi (AWD) recently.

[*** I am mentioning the car's exact model in case it matters due to tire sizes, suspension, BMW's type of AWD system etc. effect on handling etc.]

Right after the front right tire replacement, the car handled well, even at highway speeds.

The next day, since my car is AWD (I read up online about tread differences and what it can do to AWD) and also for handling in general I also decided to have the right front (the new tire) rotated to the back right (13,000 miles on that one) - I was trying to keep tread on each axle as even as possible.
My thinking of doing the rotation was because the left rear was replaced at 7,000 miles, so it has about half the wear of the original right rear (which as 13,000 miles on it).
Therefore moving the brand new right front tire to the rear and the old right rear to the front would more closely balance the four tire's tread, on a per axle basis; this was my reasoning.

However, after rotating the right side, the steering wheel vibrates slightly at high speed and the handling is 'loose' at higher highway speeds (i.e. car doesn't track as solidly as before the rotation).

NOTE (in case it matters that a tire was inflated to one pressure for 13,000 miles [35 lbs] then to 30 lbs afterwards - i.e once moved to front);
Rear tire pressure is 35 lbs and front is 30 lbs.


I know that the vibration could be due to rear tire having worn differently.
In addition, the 5 lb lower pressure once it was put on the front may also make a difference.

Questions / ideas:

Solution 1:
a) I guess, maybe the right tires should both be rebalanced, especially due to different
pressures from when they were originally balanced?
b) Will the vibration (and handling looseness that started right after rotation) subside after a few hundred miles when the front right tire adapts to its new position and new lower pressure (30 lbs vs. 35 lbs before rotation)?

Solution 2:
Keeping in mind that the remaining tread for each tire is, approximately, as follows:
New tire (was on right front, now rotated to right rear): almost 5/16"
6,000 mile old tire (on left rear): approx 4.2/16"
Other two (original) tires (one on right front; other one was on right rear and was rotated to right front): 3/16"
would anyone recommend just rotating them back the way they were?
Due to AWD, I was trying to keep the two tires on each axle as close as possible in terms of tread depth, BUT I want handling to be better (I don't mind if it take a couple of hundred miles for the tires and handling to adapt, as long as it DOES happen).

Any tips / suggestions would be greatly appreciated.

Thanks!

[redk9258]

You should ALWAYS replace tires in at least pairs, all four are better.

[Feu]

You should ALWAYS replace tires in at least pairs, all four are better.

Thanks for the feedback!

Some comments about that:

- I only replaced one tire (developed a problem after encountering a road asphalt defect), because the other three have ample tread left.
In fact the left rear was actually replaced only 6,000 miles ago, which is why I decided on the rotation, so that the new one would be on the same axle as the left rear.

- The handling was fine after replacing the tire before the rotation, which i did on the day after the replacement.
The handling only deteriorated after the rotation, probably because (I am guessing) the new and old tires (that were rotated) were balanced when they had 30 and 35 lbs respectively.
After the rotation (right front to back), I had to have the pressures swapped.

Wouldn't a relatively large change in tire pressure (5 lbs in this case) AFTER the balance throw off the wheel balance?

[tazdevl]

Yes, lower pressure could affect handling. Also, there's no guarantee that they balanced the wheel correctly. Other thing to consider is if you knocked your alignment out.

[Feu]

Yes, lower pressure could affect handling. Also, there's no guarantee that they balanced the wheel correctly. Other thing to consider is if you knocked your alignment out.

Thanks a lot for the feedback taz!

The reason I assume that balance (for its original pressure of 30 lbs position on the front) and alignment * were both okay is that the car felt fine, even at highway speeds, after the replacement (day 1).
There was no unusual pulling or uncomfortable handling.

However, after the rotation (day 2 till now) the handling seems to have changed drastically at high highway speed.

Yesterday on the major highways (commuting home from work) the car had a very uncomfortable tendency to feel, at times, like it was being alternatively pulled left and then right, but it was more like an unstable feeling, than just a traditional front end pulling.
I know the tread and/or tire has to adjust, but this wasn't a traditional pulling to one side sensation.
There could have been some wind, but still, this didn't feel right / normal.


* With respect to alignment:
I was nevertheless considering possibly having the alignment done due to hitting a few nasty potholes over the winter; however, considering how well it handled after the tire replacementr (BEFORE rotation) that may not be necessary.

First I want to get the tire, balance and rotation issues resolved.

[CowboySlim]

I am not familiar with the drive train on that vehicle. However, unequal diameters, or effective circumference, on a driving axle that has a torque transferring differential can lead to problems like binding, grabbing, snapping and torque steer.

You always have a matched set on a drive axle. With AWD, I presume that both are drives.

[steelly]

I am not familiar with the engineering of your vehicle, but since I was a kid (1970s) I always rotated at 5000 miles period! Front Wheel drive is 3000 because the tires wear harder due to drive axle, steering and brakes.
I would never just buy one tire; replace in either pairs or all four at the same time. Keep the extra for an additional spare.
I would leave the rotation the same for now, but would take it in for high speed balancing: This should cure your problem!
When you buy four at a time, rotation and rebalance is free, and mandatory to keep the warranty in effect!

[tazdevl]

Slim, AWD cars typically have some form of bias. For example, my Infiniti FX has RWD bias until it detects slippage then it can vary up to 50% of the power to the front wheels via the differential and vary power to each individual wheel via the brakes.. Other car manuf have a FWD bias. I believe BMW's system works the same.

FeuCouple things... I'd check pressure and have all 4 tires rebalanced.

Before you do that though, check to be sure they are all on the wheels with the correct orientation (facing the right way) since they are directional (remember that from my 328i convert). That could also be the source of your problem, epecially if you put on your spare. There should be some arrows on the sides of the tires indicating with direction they should be rolling.

If you have a tire replaced, you want to be sure you put the new one on the primary drive wheels and depending on how many miles you have on the set, might be a good ideal to just get two. So in this case you might need to get another tire and put both on the rear.

If you have over 7500 miles on the previous set, wear etc would support Slim's perspective. I usually got 22K out of my tires on my BMW. So if you're at 7500, 1/3 the tread is gone. Only way to know for sure is to get your tread depth measured.

Did buy the same kind of tire as the others?

Only other thing is that if you nailed a pothole pretty hard or took a chunk out of the wheel, they probably missed that when they were balancing the wheel. Sometimes they need to put a weight on the inside of the wheel.

[Feu]

Thanks for all the feedback guys.
I didn't have time to check the thread before running off to the tire place during my lunch break.

Outcome:

One rim was slightly off (they didn't, however, say it needed to be replaced)
but they felt the tire on one of the wheels had two slightly raised portions.
The guy was honest enough to say he wasn't sure.

He did think it might be a good idea to get a new tire (he said that is what he would do).
That, along with the fact that I had already been considering getting a 2nd new one (to keep the tread per eaxle as even as possible - the oldest ones had 13,000 miles on them) was enough to make me get one additional new tire.

So outcome:
- one new tire
- they also changed the balance on one wheel [the one that was replaced last week (they didn't charge me for the balance; they also did the rotation for free last week which was nice).
- they checked balance on the two old ones

They were going to put the new ones on the rear, but I asked for them to be put up front since the handling and road feel is mostly through the front wheels since they are connected to the steering.
Besides, the two older tires had a surprising amount of tread left.
One has 13,000 miles; one has 7,000 miles on it.
My AWD system car is a 38 (font)/62(rear) torque split.

I will have to test the car on the highway at high speeds tonight and tomorrow during the commute to and from work.

I said if I wanted to go all out I could get all four new ones (e.g. in case of other defects).
He said "I wouldn't do that". See how it goes with the two new ones.
At least he was NOT trying to sell me anything I didn't need (alignment, four tires instead of two, new rims).
I saw them tell someone else she needed an alignment; and the manager told me that another gentleman who owns a BMW (low profile wheels M3 or M5) had to have all 4 rims replaced when it turned out that potholes had warped all four.

Finger crossed!

Regarding two comments above:

- My tires are not unidirectional (they are Continental Conti Touring Contact).

- You mentioned you got only 22K miles.
Remember your tire wire depends largely on the model of the tires (some last much longer than others) and also on diriving style (hard conrners, hard acceleration, hard stops and road surfaces.

I'll check the treadwear numbers later

With the amount of driving I do for work, I'll need new tires relatively
soon (1 year or so) anyway.
Surprisingly even the oldest of the four tires (13,000 miles) has a lot of tread (more than 70% I would say; will measure it later).

EDIT:
I think when I measured them in the middle, after getting the one new one last week, the remaining tread was as follows:
New one: 5/16 "
One with 7,000 miles: 4.2/16"
Oldest two: a little over 3/16 ".

So now it should be
front axle: TWO with 5/16 (both brand new)
rear axels: one with 3/16 and one with 4/16 " The difference seems less.
I'll do some measurements this evening.

I am hoping I don't need any new rims...
I tend to doubt it, since it was very good right before the rotation and haven't hit anything or done anything unusual since then.

If worst comes to worst, I'll get it balanced elsewhere in case their balancing machine is off (I noticed they were trying to get the right adapter to get the wheel to fit right, but they did seem to haev found it.
I saw the balance readout was 0 (emaning no issues).

At least now the front steering much less loose even at low speed, so that is a plus.
But the handling is something I can only test at high speed, since that is when the issues became most apparent.

Fingers crossed.

[tazdevl]

My BMW had Z rated tires, hence the low tread life. BMW must have put V rated tires on your car.

I would have moved the tires to the rear. The bulk of the power in your car is going to your rear wheels, will help in cornering etc... epecially in crappy conditions, up to you.

I can't remember the rule of thumb on tires, but those life expectancy measurements seem on the high side. I replaced my FX tires at 3/16ths.

[Feu]

My BMW had Z rated tires, hence the low tread life. BMW must have put V rated tires on your car.

I would have moved the tires to the rear. The bulk of the power in your car is going to your rear wheels, will help in cornering etc... epecially in crappy conditions, up to you.

I can't remember the rule of thumb on tires, but those life expectancy measurements seem on the high side. I replaced my FX tires at 3/16ths.

Rules of thumb, thanks to tirerack.com and other sites:

I think 1/16 is legally considered to be worn out.
However, that is too low, especially since resistance to potential hydoplaning is virtually zero at that point.

I have read that 1/8" is the minimum for wet traction and 3/16" for snow.

Regarding the handling and putting the new tires on the back.
I originally did just that. I rotated the single (at the time - i.e. last week) tire to the back, but that is when the jittery handling problems started...
Besides (I can take photos of the rear tires) the tread on the rears is in great shape (evenly worn) and has ample tread left.
I am surprised it is "only" 3/16 on the lowest tire, because I have had at least one previous car where I replaced them with much less than 3/16, at least it seemed that way visually-speaking, and they didn't give me any issues just prior to replacement.

I just measured them again, and the brand new ones don't seem much deeper than the older ones (13,000 and 7,000 miles).
I used a penny and the differencec was small.

The treadwear rating is 360, which is very high relative to other tires I believe.

Temperature and traction grades are both A (A is best for temperature, A is second best [AA, A, B, C] for traction. This is for those reading this who are not familiar with these ratings).

Next time I replace all four, I will go with a different model and.or brand.

These are my exact tires:
http://www.tirerack.com/tires/tires.jsp?tireMake=Continental&tireModel=ContiTouringContact+CH95&vehicleSearch=true&partnum=055HR6CH95BMW&fromCompare1=yes

They received very good performance numbers in reviews.
Their weakest point was snow performance (6/10), with treadwear second, but not bad (at least not numerically-speaking.
That makes sense; I wasn't too impressed, compared to what I expected from an AWD tire.
The good thing is that winter is over and I will be driving 270 miles a week for my 3 days of work a week (work from home the other two).
That alone is going to be close to 13,000 miles in a year if you subtract for vacation and add for driving to get lunch or go shopping during lunch hour.
Add my normal driving mileage and I will be ready to replace them probably just in time for winter (or sooner, which is okay too of course)

[b]
I will probably get these "ultra high performance all season" Contis next time and they even have good (actually better than mine IF the numbers are comparable between different categories) snow performance!:
http://www.tirerack.com/tires/tires.jsp?tireMake=Continental&tireModel=ContiExtremeContact
They are also very affordable for 205/55 R16 tires!
$88 at tire rack, so maybe $110 + tax at tire places.
Mine were $99 each plus $19 each for balance, valve, state disposal fee etc.

[Feu]

Update:
Now that I have gotten two new front tires and had balance checked (redone on one), it does feel a fair amount better than the other day, but something is still off.
I am going to call the dealership's service department (they have a free 10 point safety check that includes checking tires and suspension with free car wash).
I'll describe my situation and ask them to also (in addition to suspension) check:

1) rims for defects and rear tires for bumps and/or imperfections / defects
2) balance of all 4 wheels (probably not the issue)
3) alignment (car feels like wheels might be pointing in slightly different directions).

I think the items listed in 1) or 3) are the most likely culprits.

Maybe they can have someone test drive it at 65 MPH+

Thanks for the feedback so far.
Keep it coming.

[Jim]

Dealerships are terrible about keeping their balancers calibrated. Their employees often times aren't using them properly either no matter how long they've been using them. Their machines can also only balance down to 1/4 of an ounce while the machines used at the plants are good to 1/8 of an ounce. When I first started out Sportscar racing I relied on dealerships for balancing race tires. I got so frustrated with the wheel shaking or tire thumping at 120 MPH I bought a tire balancer myself. No more problems.

Bad alignments are not going to cause immediate shakes and vibrations. They will cause abnormal tire wear over time that can lead to symptoms after a tire rotation.

I would put all the "wheels" on the same corner they came off of before your rotation. Put the wheels on and use a torque wrench in a star pattern to torque them on. If you still have the vibration then you have a balance issue because you didn't before. New tires are not going to cause shakes or a shimmy unless they are improperly balanced. You need to eliminate some variables here.

As was mentioned previously, make sure they didn't rotate side to side if the tires are directional. If they are, they will have an arrow on the side pointing in the direction of rotation.

[Feu]

Dealerships are terrible about keeping their balancers calibrated. Their employees often times aren't using them properly either no matter how long they've been using them. Their machines can also only balance down to 1/4 of an ounce while the machines used at the plants are good to 1/8 of an ounce. When I first started out Sportscar racing I relied on dealerships for balancing race tires. I got so frustrated with the wheel shaking or tire thumping at 120 MPH I bought a tire balancer myself. No more problems.

Bad alignments are not going to cause immediate shakes and vibrations. They will cause abnormal tire wear over time that can lead to symptoms after a tire rotation.

I would put all the "wheels" on the same corner they came off of before your rotation. Put the wheels on and use a torque wrench in a star pattern to torque them on. If you still have the vibration then you have a balance issue because you didn't before. New tires are not going to cause shakes or a shimmy unless they are improperly balanced. You need to eliminate some variables here.

As was mentioned previously, make sure they didn't rotate side to side if the tires are directional. If they are, they will have an arrow on the side pointing in the direction of rotation.

Thanks a lot!
They are not directional (I did mention this in an earlier post but I know this has become a long thread and my messages themselves are lengthy.

The biggest problem isn't vibration per se.
It is more of a jittery handling (as if car is being pulled of its course in that two wheels are pointing very slightly in different directions therefore noticeable at higher speeds (65-75+), but NOT a pulling-to-one side sensation which would almost certainly be alignment) and bumpy ride
as if the tire is out of round or rim is off a bit?

I definitely need to eliminate some more variables.
I eliminated some by having two new tires put on front and all four balanced and/or checked for balance (two that didn't have new tires were fine).
I may go to a different place (dealership makes sense, since they already have this free 14-point spring checkup special with free loaner and car wash, and I could kill two birds with one stone) and get a 2nd opinion.

The three possibilities I see are:
- minor rim defect (due to hitting a few potholes) on one or two rims
- tire defect (on one of the rear tires)
- alignment

Maybe the car handling wasn't quite as good before this all started as I remembered it being, BUT I am 90% sure that it WAS much better, based on my drive home last Thursday where there was surprisingly little traffic and the handling seemed fine.

I assume the rims be inspected / checked without dismounting the tires.

[Feu]

Quick update:

Took it to the dealership (combined it with a free 14 point safety check that they had e-mailed me about, which includes a free wash).

They couldn't find anything wrong:
They did a road test and it tracked straight).
They also checked the htings I had requested,
- rims (no issues found)
- tires (tread was fine they said)
- suspension (no problems).

They did NOT recommend an alignment (no doubt based on the fact that it was tracking straight according to the road test) - I had said if nothing else was found, maybe I should have it aligned when she asked if I wanted the alignment done in response to my asking that it be checked - hit those three (big) potholes recently) to see if that would help.

The good news, other than peace of mind in that they checked the suspension, rims tires etc., is that they may have finally resolved an annoying intermittent whirring / chattering noise that they could never find - they even replaced a rear suspension component last year (under warranty).
I had given up on bothering to get it fixed after several attempts including road test with a BMW NA tech specialist.
When the service advisor asked today if there was anything else after
I listed the things that I wanted to be checked with respec to the perceived handling issues, I mentioned the noise...

They noticed today that one of the brake backing plates was slightly bent, so that was bent back (I guess it may have been causing some very slight friction that led to the noise).
It was only a noise, didn't affect anything mechanically, but was annoying.
Hopefully it is gone for good now.


I will keep an eye on the handling and see if it is maybe related to specific spots on specific highways I take to work; I did notice that it was much better on the highway (not one I commute on) near the dealership on the way there this morning.
I just never noticed it acting jittery (quick left to right sensation) before.

Anyway, thanks again for all the tips and feedback.

EDIT It did cost $50 odd for the reshaping of the (brake) backing plates.
Hopefully it did get rid of the noise, although the noise was there
before I hit the potholes.
Regardless, I don't want the backing plate interfering with anything and for $50 it isn't worth worrying about when or where it might have occurred.

[Feu]

Probably the last update:

I picked car up tonight.
The noise was gone, so I thought great!
Then the noise came back when I drove it home from my parents' place.

The good news is that the handling does seem very good.
Maybe I was over analyzing it or just driving on bad highways.
I took it up to a high rate of speed (understatement) briefly on the highway near the dealership just to see how it did and it didn't flinch.

I can live with the intermittent noise (seems to occur 40% of the time), which isn't very loud - sounds like a chattering/whirring/ticking kind of noise.
The handling was my main concern and that seems to be fine now.

They also washed the car, rims and tires and vacuumed the car.
It looks ten times better after the BMW service department wash than after the $8.50 car wash down the street which left a bunch of spots last time (first and last time I go to that car wash. I went there because it was close and I was on my lunch hour); they missed a bunch of spots completely.

[bill]

Probably the last update:

I can live with the intermittent noise (seems to occur 40% of the time), which isn't very loud - sounds like a chattering/whirring/ticking kind of noise.

Are you certain that the noise is coming from the brakes or drive train? Do you hear the noise at a specific driving speed? Automatic or manual transmission?

[Feu]

Probably the last update:

I can live with the intermittent noise (seems to occur 40% of the time), which isn't very loud - sounds like a chattering/whirring/ticking kind of noise.

Are you certain that the noise is coming from the brakes or drive train? Do you hear the noise at a specific driving speed? Automatic or manual transmission?

I am not sure and neither are they (BMW), which is why it hasn't been fixed after four or five visits.
I don't know if it occurs at highway speeds.
I am trying to think if I ever observed it at highway speeds.
It has a manual transmission.

I can, for the most part, live with the noise;what I can't live with is the &^$$& potholes!
I was so happy this afternoon, since the car was handling very well.
Then I was driving home tonight at 1 AM on the Garden State Parkway (obviously very dark); after about 90 seconds I hit a (nasty?) pothole on the edge of the lane (right on the line marking between the two lanes I think).
It was enough to undo one of the radar detector suction cups on my windshield, although the cups have sometimes come off by themselves at times overnight during temperature changes or during the day during temperature changes..

The rest of the 45 mile drive on the GSP I didn't even SEE one single pothole (I was checking to be safe)!
Talk about bad luck!!!!! I just happened to be in that part of that specific lane at that specific spot on the highway to hit that one nasty pothole.
It was probably the ONLY real/serious pothole on the 45 mile stretch of the GSP I was on tonight.

The car was handling so nicely and everything had just been checked out
yesterday.
When I got home, I checked the sidewalls of the front and rear right side tires and also the rims; I didn't note any defects.
The handling seemed okay after hitting the pothole; I am hoping I got lucky and that I don't need to replace yet another tire.
I am going to try not to worry about the alignment or suspension; I am working on the assumption they are fine, since the car drove well after hitting the pothole, but the uncertainty is unsettling after the full checkup just yesterday!
I think / hope, based on the fact that the rims and suspension were found to be fine after the three previous potholes in the past three weeks, that this one ALSO did NO harm / damage to the suspension or rims (bent, warped etc.)..
Another tire going bad I can deal with, since at least I would know it (bulge, low pressure, flat etc.) and a replacement would be a 100% cure.
On the other hand, damage to the suspension or alignment isn't something you can always tell, since it is subjective and there are usually NO visual cues...
The lack of a bulge (so far) or any other defects on the tires, rims is somewhat reassuring.


It is VERY frustrating that they don't patch these things up, especially on a MAJOR TOLL highway, where small cars (13 - 14 inch wheels and tires e.g.) can get major damage (to rims, suspension) and/or get into accidents.
Nice to see our toll dollars at work (sarcasm).

Sorry for the rant, but after worrying about the handling, getting everything checked out, only to be unlucky enough to hit the ONE pothole...

Maybe the sound of the car hitting it was worse than the actual effect of hitting the pothole???

Unfortunately I didn't even see it due to it being dark, my paying attention to traffic etc. and not having been staring down at the road for potholes obviously, so I don't even know how big it was and I obviously c ouldn't turn around to check it out for peace of mind, as I could have on a regular two-way road.
[b]
I don't know what would have been worse, hitting it at 80 or at 50 MPH e.g.

These are the times I wish I had a vehicle with 20 inch rims and tires (not low profile of course), so they would literally go right over major potholes
due to their large diameter.

[LoneWolf]

From my experience, 13 to 14 inch rims are LESS susceptible to dents and dings than 17 or 18 inch ones, not more. You have a lot more tire between the road and the rim to absorb the impact.

I have (only for a few more weeks, as we just bought a new car to replace it) a 1994 Acura Integra GS-R. I had a lot more issues with potholes with my 17's than with the stock 15's. The only way you could be at higher risk with a small rim I would think is if you had a pothole big enough to take in the whole wheel/tire at once. And I live in Michigan where you can bathe small children or lose your pet dog in our potholes.

Just bought a 2004 Honda Civic EX sedan with a hair under 12,000 miles on it. I'm glad I'm back at 15" wheels, not only for that reason, but because quality tires are far less costly. Any vehicle with huge rims, you pay through the nose for tires, even moreso if they're not low profile...and you're likely to pay through the nose for gasoline as well, due to the type of vehicle that uses them. I am so glad to now have a car rated 31/38 for mileage on regular gas; I loved the `Teg, but with a 35-mile commute, it was starting to get costly even though it got good mileage for the car it was.

[bill]

Feu

This could be a long shot...

I asked because the noise, "annoying intermittent whirring / chattering noise", could be an AC compressor cycling on and off when it's low freon and oils. I don't know about BMW but the AC cycles during the winter months (defrost setting) on my GM vehicles.

Chattering or clicking sound= low freon, compressor trying to cycle.
Whirring sound= low oils (mixed with freon) or the beginning of bearing failure.
It would be difficult to hear the noise during medium to high driving speeds.

Or

The manual transmission throw out bearing, pressure plate and springs. The next time you hear the noise try stepping on or release the clutch and notice if there is any difference in the sound.

[Feu]

Thanks LoneWolf.
Enjoy the new car! Try to stay away from toad defects.

That is exactly what I meant, IF the hole is wide and/or long enough to take in the whole wheel (which is why I mentioned the smaller diameter).
Otherwise, the aspect ratio is the only thing that matters (low profile tires are multiple times more likely to have rim damage).


Thanks for the suggestions on what it might be BigMonkey!

I once thought that depressing the clutch helped, but I have (recently)
confirmed that depressing the clutch doesn't do anyhting to eliminate the noise.
However, depressing the brakes immediately stops the noise, even when the car is still moving at a reasonable pace.
It comes back when I release the brake pedal.

Regarding A/C. I didn't have the A/C on.


I just noticed that the kid (even though he took his time) didn't get the cold pressures right.

The front two tires are about 28.5 instead of 30 lbs.
The rears at 33 and 31.5 instead of 35.
Not even close.
The previous time they got the pressures perfect (not even 1/2 lb off); otherwise I would have double checked them right after leaving the tire center.
Come to think of it, I am suprised the dealership didn't even check the tire pressure, since checking the tires was part of their 10 point checkup.


I hope the lower pressure didn't hurt when hitting last night's pothole.
I think I got lucky.

I'll fill them up today and then on the way home test drive it again.

I checked the tires and rims again (daylight now).
Still no bulge. I didn't detect any scrapes or damage to tire sidewalls.
The rims have (pre-existing) little nicks, but in the middle, so definitely not from potholes. The edge of the rims (where the balancing weights are attached) are flawless.
Hopefully I got lucky last night.
Fingers crossed.
The noise was loud and the suctions cup came off, as mentioned, but
I believe that it wasn't worse than any of the previous potholes, especially based on tires and rims not having any damage.
I guess suspensions are built very well; they can take a hit like this.
The fact that the pothole jostled the car (usual thump) but didn't throw it off course, leads me to believe that it probably wasn't all that big...

Last night's at 1 AM, was the first pothole hit at high highway speed though.

I don't mind if it did need a new tire or alignment (won't be happy of course), as long as the suspension and steering are intact, due to the objective versus subjective nature of thoise two types of problems.

Thanks again for all the feedback guys!

[Jim]

Your noise is in the brake system if it consistently disappears with pedal application. You might be slightly dragging a pad. It could be hanging up on the knuckle upon release. I'm not familiar with the brake design BMW uses so it's hard to comment beyond that.

Generally speaking the more sidewall you have the better you'll weather a pothole. A 205/60R14 tire will give you a better chance than a 205/50R15. Of course the truck tires on my Hemi RAM stand a better chance than any of the 14-16" tires on my cars.

Jim

[Feu]

Your noise is in the brake system if it consistently disappears with pedal application. You might be slightly dragging a pad. It could be hanging up on the knuckle upon release. I'm not familiar with the brake design BMW uses so it's hard to comment beyond that.

Generally speaking the more sidewall you have the better you'll weather a pothole. A 205/60R14 tire will give you a better chance than a 205/50R15. Of course the truck tires on my Hemi RAM stand a better chance than any of the 14-16" tires on my cars.

Jim

Thanks Jim.
I'll have them check the brakes next time I bring it in.

Regaring the profile, I have 205/55R16 tires, so my rims are fortunately not nearly as low/close to the "pavement" as a sportier car's tires or a model with the sport option (bigger, but lower profile, tires).

By the way, the car suspension and alignment seem to have survived pretty much unscathed; thankfully!
I think the sound was a bit worse than the actual hole...

I did a nice highway test drive yesterday. The weather was great 75 [well above the average for this time of year, which is about upper 50s] and sunny, so checkng the handling out was also a good excuse to hit (no pun intended) the open road.

Yes, a truck is always a better bet on weathered roads.

I feel sorry for motorcycle riders. They have to be extra careful so as not to hit a pothole (or other road imperfections) so as not to possible lose control.

Their one advanatge, IF they see the pothole in advance, is that they can
steer around most potholes without worrying about colliding with traffic in the lane next to them.