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Hi all. I'm trying to perfect my E60 M5's handling by getting it up to factory spec. I've done a lot of modifying over the years, but in my older age I've decided BMW makes them how I like them. Just my opinion.

Anyway, I've replaced front thrust arms, lower control arms, and entire tie rod assemblies, as well as rear ball joints. I've always just gone nuts and replaced every last thing I reasonably could. This time I thought I'd do it incrementally to try to glean what change has what effect...all the while knowing I'm spending a lot on alignments along the way. All Lemfoerder except the thrust arms as I opted for the Meyle with the HD bushings, as I have in the past.

Tires are stock sizes...Continentals. I forget what model, but it's the one Tire Rack always recommends. And they are new. Maybe 1000 miles on them.

The steering demonstrates no play...the slightest move of the steering wheel yields a slight change in direction. But the car itself is kinda slow to respond. I believe that aspect of things is probably due to wear in the rear upper control arms, guide links, and integral links. Those are getting replaced next week.

I'm coming off of an 08 550 M sport which I had set up perfectly. The thing responded like crazy. So I have an idea in my mind of what this M5 should feel like and it's not quite there. In fact, unless I'm talking to a serious enthusiast, I'd recommend the 550i M Sport, or 535i M Sport for the mod guys over the M5. Just less quirky and doesn't require IT training to check the oil. Sorry but the whole oil thing is stupid. Granted...read the manual, right? But what is supposed to clue me into the fact that the M5 requires totally different treatment in terms of oil? There should be a notice on the oil filler cap..."please refer to manual for non-standard oil measurement procedure." Sorry, I digress.

This whole thing is poorly worded so I'm just going to start listing things.

1) I still feel a vibration in the steering wheel at around 65mph even though all the arms and links up front are brand new.
2) although the front wheels do change direction with the slightest input from the steering wheel, the steering feels kinda light in the first few degrees off center and shakes a bit, there as well.
3) I hear no noises from the suspension at all
4) I noticed that unlike EVERY other BMW I've owned, staggered wheels or not, this one says the tire pressure front and rear are supposed to be the same. I'm accustomed to more in the rear, less in the front.
5) I don't have active steering
6) I feel like the M5 actually rolls a bit more than the 550i with Automatic Roll Stabilization. They say that's "handled with EDC" but I don't know.
7) doesn't seem to matter whether EDC is set to light steering comfort mode, or heavy steering sport mode.

So I wonder what the heck is causing the vibration. Wheel out of balance/out of round? My tire guy is historically really great and I've never had a bad job from him. The vibration is not super severe, but it's there. It feels that as I move away from center I feel the vibration a bit more for a few degrees, and then once the suspension is loaded one direction or another, it's gone.

Why is it that every BMW I've ever driven feels worse on-center than when I start throwing it around? Definitely inspires me to drive like a maniac. lol

Does this sound like a steering rack issue? In looking around for symptoms, it seems most folks describe clunks and other anomalies that can be clearly felt and heard. Mine has absolutely none of that.

Curious to hear thoughts on this!
 

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Not steering rack, probably too much toe in, I like toe out, gets darty but feels like in a smaller car on autocross course.

many times tires are not round from manufacturing, check with installer if road force balance Ended up over 12 lbs , if so have tire rotated on the rim for high spot marking to match low spot mark on rim. If still too much road force have tire exchanged.

there is no roll stabilization effect from edc
 

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Do you have a print out of your alignment settings? Camber, caster,and toe for front and rear. All that makes a big difference in responsiveness. Camber is a big contributor. With the BMW multilink design wear on bushings will cause all these things to drift, unless it's been set properly then that's causing your "lack of satisfaction" especially compared to other E60s. That said I do agree that the 535 can feel better for those that are particular to recognize that, but that's due to lower front mass, and lower unsprung mass also.

You need to have your tires Roadforce balanced on a Hunter. It's a much more expensive balance job but it's designed for the more complicated problems and vibrations you're having. You could have an out of round wheel or excessive sidewall deflection, the adhesive weights also fall off if they didn't clean the area with the excessive brake dust our pads generate. Where are you located?
 

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I had a slight vibration at 60ish mph. Wheel weights were falling off after some hard driving (found them sitting on the garage floor). Went back to the tire shop to get them added back on. Week later vibration again... more weights had come off. So I had to use high temp tape (old racers trick) to hold them on. Just something to consider.

Maybe you have someone local you can swap wheels with to try out?
 

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Discussion Starter #6
All good thoughts, thanks. I don't have my alignment printout, but I did look at it and I definitely recall every spec was set dead center within the tolerances, as this guy always does. He also has a hunter road force balancer. These guys are a private collision shop and work on high end cars a lot. I've used them for 10-15 years now, so I have faith in their work. They're super anal about keeping their alignment rack maintained and will protest if a wheel or tire shows irregularity. So I'm generally satisfied that the alignment is good.
But everybody screws something up eventually.

I wonder about weight balance, though, compared to the 550i. How much lighter is the N62 than the S85? The SMG trans has to be lighter than the sport automatic I had in my 550i, no?
 

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The s85 has a lot more aluminum in front to keep 50/50 weight distribution, starting with aluminum subframe instead of steel.

Thus very small weight difference
-550i is 3,936 lbs
- m5 is 4,012 lbs
 

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I have my own Hoffman alignment machine and Hunter Roadforce balancer, because I'm also very particular to ride and handling stuff, but that's what happens when you used to do vehicle dynamics stuff for a living and you have extra space. That stuff drives me nuts, but I've been polluted. It's really hard to have the vehicle dead set on every spec in the center of the range, even from the factory, so not really fair just to blame your mechanic. Even setting toe, it's very easy to have it set perfectly and then you jounce the vehicle like you are supposed to and then the numbers are different again...

As for tires/wheels, weights do fall off, tires will wear unevenly and it's balance will change over time. Most people aren't that sensitive to that so it really doesn't matter that much. I noticed some imbalance a few months after I went back to my summer tires/wheels on my DD (not M5, its an SUV). Everything was perfectly balanced last fall before I went to winter tires/wheels. I noticed some slight vibration and was like that's weird, wasn't like that before. I did a balance audit and it was off by 1 oz and all the weights from last time were still on...

If it really bothers you then have your tires and wheels audited on the hunter again. The tire and wheel swap thing as mentioned is also a very good way of isolating the issues. That's what I've done before also.
 

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The s85 has a lot more aluminum in front to keep 50/50 weight distribution, starting with aluminum subframe instead of steel.

Thus very small weight difference
-550i is 3,936 lbs
- m5 is 4,012 lbs
Assuming all alignment and other mechanical stuff is sorted out. I would expect the 550i to feel very similar to the M5, but the active roll bar thing does have an effect. Also the larger, heavier M5 wheels/tires do affect steering response. Same with the larger brakes. It's physics. Larger tires and wheels have a big drawback, but if you're doing track stuff then you have to live with the trade off to get more lateral grip.

The S85 is the heaviest by far- 240kg/ 530 lb dry weight. If they went with steel bore liners it would add quite a bit more, but M division could care less about long term durability if it weren't already obvious by the genius oil clearance specs.

The N62 is 213kg/ 470 lbs.
The N52 (the I6) is 130kg/ 287 lbs this makes a MASSIVE difference in how agile the car is.

All e6x platform vehicles have an aluminum front subframe structure AFAIK, maybe I'm wrong. The M5 does have appear to have a unique subframe based on the markings I've seen. The front subframe is a massive determining factor in terms of front crash performance. There are no structural body in white differences between the M5 and standard E60. The aluminum M5 specific front fenders are not structural. There are alot of reasons why having a different front subframe material construction would be a massive complication for the overall program. Tooling costs to development, crash testing to validation. That would be a very odd choice for any OEM to do on the FRONT subframe for a unibody platform. Rear subframe is a bit of a different matter, but still massively complex. Aluminum to magnesium is a different story, much more similar in material properties and production.

BMW's I6 (naturally aspirated) is generally regarded as THE industry benchmark. Similarly for D/E segment vehicles (BMW 5 series/ Audi A6/ MB E class/Cadillac CTS, etc.) the 6 cylinder version of these vehicles always are the benchmark for weight targets and ride and handling. Those versions are as close as you can get to 50/50. the weight difference I described above is hugh. The V8 (or V10) versions are always the "flagship most powerful model because we can shoehorn in the biggest engine we can and charge the most amount of money for the platform". These are muscle cars that follow the tried and true formula from the 60s, mass production car with monster engine. It is not a sports car or exotic despite the engine, IMHO BMW's only real attempt at that was the M1.

The E60 M5 is not 50/50, much closer to 53/47 in stock form. I've not cornerweighted my cars but they are pretty much stock, and I'd venture to say that I'd have to add quite a bit a weight to the rear to get it to 50/50. There's not alot you can do to the front of the M5 to reduce weight, the whole front body structure in front of the firewall is already aluminum. Carbon ceramic brakes and 18" wheels would be the biggest weight loss items you could do.
 

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Discussion Starter #10
My God I wish I at least had a lift. It would save me SO much hassle and money, and money, and money. But alas I need a space with a high ceiling

Unfortunately I don't have a resource for swapping wheels/tires. I'm also currently not at home. I live in Maryland, but my mom is in Chattanooga TN and got Covid on her 80th birthday. It damn near took her out (common cold my ***) so I'm watching her house and dogs indefinitely while she heals and rehabilitates. Fortunately I can work remotely.

My father, before he passed away, used a really great mechanic here who is going to look at the car next week. It'll be a valuable second hands-on opinion. He'll install the control arms, guide links, and integral links next week. Then I'll have it aligned by a reputable shop here and see where I stand.

I'm really curious about two things, though. Bearing in mind I do not track my car at all. Strictly public roads for me.
1) why do so many shops refuse to put weight in these cars when they align them? They claim it doesn't make that much difference. I can't imagine how that could be true.
2) why does the M5 call for equal tire pressure, front and rear?
 

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Discussion Starter #11
Incidentally, regarding wheels, my E60 550 had wheels pretty much identical to the M5. A slightly different pattern (not a gentle curve, but a little "kink" in the "spokes") but not dramatically and not to a degree that I could imagine would mean any material difference in mass. Also 19" with the same tires as the M5. Although come to think of it, I don't remember what tire sizes I had on there, though.
 

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Sorry to hear about your mom. These are challenging times, I hope she does well. Frankly these forums offer some of us a way to get away from much of the political and health stuff going on.

You don't NEED a lift (but it makes it easier). You need 10 inches of concrete for lift. I actually don't have one, but have some stuff that IMO works out better, but won't go into that. I have alot of floor space though. All you really need to be able to do is get your vehicle off the ground by 2 feet. 2.5 feet is enough to get the trans out with a trans jack. 3 feet to drop the engine out on a lift table. It also makes it alot easier to hop in and out of the car and you can reach stuff on the top side of the engine bay and beneath.

Some alignment shops only set the toe or only do a front end alignment. On some cars (trucks), that's all you can really do. Many times, the links or fasteners are corroded or the customer is unwilling to get new bolts. The rear toe-in cam bolt for the M5 is known to rust and snap right off. Ask me how I know. Order that ahead of time, especially if you can't have the car sit on the lift. For the E60 you ALWAYS must do a 4 wheel alignment if you want it done right. The rear toe if not properly set will affect the front end and can cause the car to dog track or pull. It takes longer and it's more expensive. That's why I asked if you had the report.

The Hoffman/John Bean/Snap On software that I use it Pro42. It allows you in the software to set driver side weight, passenger side weight and fuel tank level. So it does kind of know how to compensate it. Hunter's Alignment software is similar. Regardless, I never use those offsets. IMO there is no substitute for the real world geometry and so I ballast the weight myself. I weigh about 155 lbs. For most customers, it really won't make a difference at all. It did take me some time to learn how to properly evaluate vehicles and be rigorous and consistent, but that was part of my job. Despite what people think, the reason for proving grounds and test tracks are not for top speed tests or setting the fastest times.

I also take my time, so this remote working COVID stuff has helped alot. If it wasn't clear before I'm very meticulous and don't care to trust anyone else when I have the skills and tools to do it myself.

Re: Equal tire pressure. The tire package is developed specifically with certain sidewall stiffness specs. Therefore it's easiest to use a consistent value. BMW spec tires (with the star) do have different characteristics than the same tire by the same mfg without the star.

You can set the tire pressures to whatever you want. Most people will not have the ability to feel the differences between 28 psi or 30 psi or 32 psi. That's why there have been campaigns before to talk about adequate tire pressure. It was also a big factor in legislation to require TPMS in the US. Most people are absolutely oblivious, and that actually ironically indicates that something is designed well- something is not set perfectly and the customer can't notice. If you ever do track your car and you get to a certain skill level, you should be able to start feeling differences, but far more important to pay attention to things like vision, braking, steering, line, etc.

If you ever happen to be in the NJ/NYC area I may be able to take a look.
 

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Discussion Starter #13
Great info. So do you buy tires from BMW?
I’m pretty sensitive and do notice when things are out of whack even a little, in some cases. Mainly I’ve just screwed around with so many BMWs over the years I’ve learned what parts cause what problems. But then something changes, variables are added, and I’m back in the dark.
At what point would you expect me to need rear swing arm bushings and subframe bushings? I changed the subframe bushings in my old E 32 750iL, and in my old E34 540, and it made a remarkable difference. Although the E 38/39, and E60s have four bushings rather than two. I don’t have much of a sense for how quickly they wear.
Regarding swing arms, I was always under the impression those bushings could not be replaced and you had to buy the entire arm with the bushings in it. But now I am seeing bushing replacement kits and I’m wondering how good they are.

And regarding the first paragraph of your last response, thanks and your point is loud and clear and well taken.
 

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Don't they often use different subframes/suspensions on the all wheel drive cars? I know, for example, the old E34 all wheel drive cars used suspensions that more closely resembled those found on E36 3 series.
 

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Great info. So do you buy tires from BMW?
I’m pretty sensitive and do notice when things are out of whack even a little, in some cases. Mainly I’ve just screwed around with so many BMWs over the years I’ve learned what parts cause what problems. But then something changes, variables are added, and I’m back in the and dark.
No I avoid the stealer at all costs. Me and my family have had nothing but bad experiences with dealership service even stuff under recall or warranty. And this was true when I used to work for GM and Ford. In fact there were several instances where I knew their were known failures and the SA's and techs weren't able to fix it or reproduce it. This is quite a common complaint from those of us in the industry that lived in SE Michigan. It's not an issue that is isolated to the big 3 either. Dealerships are just not good at diagnosing and fixing things and doing it at an honest rate. They constantly screw over the customer and OEM, taking advantage of their geographic monopoly and footing the bill to the OEM or the customer as the backup.

Tirerack carries the OE spec tires, but they only do so until the batches stop. I'm not sure who was OE for the M5, I'd guess it was either conti or michlein. Tire technology/ compound formulation improves every few years. The modern compounds are far better than what was around when these cars were developed which is early 2000s. The fact that M5s were made 2005-2010 is not relevant, the ride and handling development was done in 2003-2004.

IMO the best all around UHP tire is the Michelin Pilot Sport 4S, it is NOT an all season tire BTW. However I believe that they have already end of lifed the correct OE sizes for the M5, because there just aren't very many cars with this particular size nowadays.

At what point would you expect me to need rear swing arm bushings and subframe bushings? I changed the subframe bushings in my old E 32 750iL, and in my old E34 540, and it made a remarkable difference. Although the E 38/39, and E60s have four bushings rather than two. I don’t have much of a sense for how quickly they wear.
Regarding swing arms, I was always under the impression those bushings could not be replaced and you had to buy the entire arm with the bushings in it. But now I am seeing bushing replacement kits and I’m wondering how good they are.
It's kinda known that BMW suspensions have to be rebuilt every 10 years, but that's kinda the magic with how they handle, it's pay to play. Clearly you know this from your other BMWs.

The E32 and E34 are old and the rubber bushings do degrade. I dropped the subframe on my '10 and I'm pretty sure those bushings can last 20 years, unless BMW went with their eco friendly self destructing rubber fetish. Modern subframe bushings should far outlive the useful life of the car, but since we're talking about BMW that might mean 10 years max. Subframe bushings are really for NVH, they should not affect ride and handling at all.

For the swing arms, I haven't looked at those other than a visual to look for cracks, which seem to happen on all BMW suspension bushings. Post a link for those kits. I have noticed that the front side diff bushings have cracked on my 08. Also the rear "guide link" has a boot on the ball joint that like to crack. Those are stupid expensive like $500 each side and are specific for the M5 (and Z8?)
 

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I hear you

first oil change on 2007 Tundra
Used wrong oil, half of skid plate bolts missing, scratch on door.

Have not been to a dealer since
 

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Discussion Starter #19
No I avoid the stealer at all costs. Me and my family have had nothing but bad experiences with dealership service even stuff under recall or warranty. And this was true when I used to work for GM and Ford. In fact there were several instances where I knew their were known failures and the SA's and techs weren't able to fix it or reproduce it. This is quite a common complaint from those of us in the industry that lived in SE Michigan. It's not an issue that is isolated to the big 3 either. Dealerships are just not good at diagnosing and fixing things and doing it at an honest rate. They constantly screw over the customer and OEM, taking advantage of their geographic monopoly and footing the bill to the OEM or the customer as the backup.

Tirerack carries the OE spec tires, but they only do so until the batches stop. I'm not sure who was OE for the M5, I'd guess it was either conti or michlein. Tire technology/ compound formulation improves every few years. The modern compounds are far better than what was around when these cars were developed which is early 2000s. The fact that M5s were made 2005-2010 is not relevant, the ride and handling development was done in 2003-2004.

IMO the best all around UHP tire is the Michelin Pilot Sport 4AS, it is NOT an all season tire BTW. However I believe that they have already end of lifed the correct OE sizes for the M5, because there just aren't very many cars with this particular size nowadays.


It's kinda known that BMW suspensions have to be rebuilt every 10 years, but that's kinda the magic with how they handle, it's pay to play. Clearly you know this from your other BMWs.

The E32 and E34 are old and the rubber bushings do degrade. I dropped the subframe on my '10 and I'm pretty sure those bushings can last 20 years, unless BMW went with their eco friendly self destructing rubber fetish. Modern subframe bushings should far outlive the useful life of the car, but since we're talking about BMW that might mean 10 years max. Subframe bushings are really for NVH, they should not affect ride and handling at all.

For the swing arms, I haven't looked at those other than a visual to look for cracks, which seem to happen on all BMW suspension bushings. Post a link for those kits. I have noticed that the front side diff bushings have cracked on my 08. Also the rear "guide link" has a boot on the ball joint that like to crack. Those are stupid expensive like $500 each side and are specific for the M5 and Z8.
When I inquired with BMW the Michelin Pilot Sport 4S was not a "BMW recommended tire" but the Contis I bought were. I also couldn't find the rear tires anywhere in the US. Since I'd had these contis on my 550i and I liked them, I went that direction. But I've not heard of the 4AS. I've heard of the Pilot Sport A/S which was on this car when I bought it. It's all relative, but my feeling was they were very squishy and slow to respond and not at all sure-footed. I kept them, though, because they still have some tread and winter will eventually return to Maryland. I guess I should get some wheels to put them on...or I could save my money for a clutch replacement. I've never been able to bring myself to buy extra wheels for winter tires. But I almost always wish I had some.

Here are links to the swing arm bushings. They're made by Lemfoerder and are very inexpensive. I don't know how easy they are to replace...I'm guessing not very.


Apparently the two bushings aren't the same.

The guide links for my car are not that expensive. But mine is an early build...like 9/05, I think, and the links I got are only good for cars up to about 9/06 or something. Maybe the later ones are a lot more. Makes me wonder if there's not an upgrade to be had, there, but how much difference could that one arm, in the context of an already determined geometry, actually make? You'd know better than I would. I almost always buy parts from BMA in California and they tend to be very good about that kind of thing, particularly if you talk to one of the owners. Every once in a while I buy from FCP Euro in Connecticut.

Anyway, I'm really curious to hear your thoughts about these replacement bushings. The fact that the metal cladding is incomplete makes me scratch my head. But I'm no engineer...perhaps it's a non-issue or only affects longevity.
 

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Having replaced those bushings earlier this year... as long as you have all the tools it's same as any other bushing. Just use a couple worm clamps to close them down. Now getting all the proper tools and adapters is the real PITA.

In hindsight my 90k miles bushing were in great shape. I just replaced them because they were super cheap. But they kept my car down for a couple weeks figuring out all the tooling.
 
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