BMW E90: Brake Performance and Issues

Hi everyone,

After several disastrous attempts to discuss this topic in brand-specific forums, I'm trying my luck with you guys.
I've only driven the E90 as a 330i before, and that was only on country roads. I noticed that the car turns in very willingly when braking, but I didn't find that negative, and our E60 (5-series) does the same thing.

To the extent that the following statements refer to experiences of my father, who asked me if I didn't know what was causing it.
He often rents the versions with smaller engines (320i, 320d), and he has already experienced quite a few problems on highways *specifically* with these types of vehicles.
On a perfectly straight highway with uniformly grippy asphalt, the car tends to become difficult to control and its rear end may suddenly swing out, even with only half of the braking force applied (without ABS intervention). The direction in which this happens is largely left to chance, especially at speeds above 140 km/h.
The behavior was observed in a 320i. My father experienced the same effect in his 320d. However, in his case, it happened on wet pavement. There was a slight amount of aquaplaning, and he couldn't regain control of the car. He managed to avoid hitting the guardrail, but ended up going into the grass with a 720-degree spin. The ESP system only starts intervening when the situation is practically beyond saving. Both cars were practically new and had brand new tires, although the tires had been sufficiently broken in to rule out such effects.
The vehicles were each equipped with run-flat tires (both summer and winter tires; I can provide the specific models if needed).
I didn't read anything about that in the tests. Only on a very detailed Spanish review website was it mentioned that the E90 is more prone to drifting and bouncing on uneven asphalt compared to, for example, an A4.

http://www.km77.com/marcas/bmw/2005/serie3/330i-p/t01.asp
http://www.km77.com/marcas/bmw/2005/serie3/320d-p/t01.asp

I suspect that the issue is somehow related to an incorrect suspension alignment. I've read about similar problems with uneven tire wear in other forums. It wouldn't be the first car delivered from the factory with incorrect camber settings or something like that.

Well, maybe someone else can share similar experiences -> Sudden wheel lockup under optimal conditions, but at high speeds. The faster you go, the less pedal pressure is needed to trigger the effect. This happens without any ABS intervention.
"The ESP and other systems were all fully activated. However, even our Lupo, without ESP and with an 80:20 weight distribution, wouldn't exhibit such behavior."

Regards,

Olaf.

I remember that effect from my old Volkswagen Golf I. Mine didn't even have a rear axle adjuster, so it was very front-heavy and extremely light when empty, resulting in significant differences in the weight distribution between an empty and a full car.
However, I can't think of anything truly helpful right now.

It's a 5 (out of 5).

http://www.n24.de/lifestyle/auto/?n2005102118422700002

But maybe there are parallels there...

How many crates of beer were back there? I don't understand Swedish!
We have an E60 model car in the family. I drive it quite often as well.
I've never experienced this kind of driving behavior from this car before.
Not loaded!
However, I only know the E60 with Active Steering and Dynamic Drive as a 530i, and WITHOUT run-flat tires.
The dynamic driving feel is a bit unusual near the limit, as the car doesn't initially roll much. Just before reaching the limit, some body lean is allowed to regain grip on the outer wheels. Then it's suddenly over. It takes some getting used to, but the behavior at the limit is different from a regular car without Dynamic Drive. I haven't had an E60 without it for comparison, though.


"Thank you for the link anyway."

Olaf.