Bimmerfest - BMW Forums

Bimmerfest - BMW Forums (http://www.bimmerfest.com/forums/index.php)
-   E46 (1999 - 2006) (http://www.bimmerfest.com/forums/forumdisplay.php?f=98)
-   -   325xi with strange interstate speed 'floating' problem (http://www.bimmerfest.com/forums/showthread.php?t=662651)

Steelsmitty 12-06-2012 06:34 PM

325xi with strange interstate speed 'floating' problem
 
Hello everyone,
New to the group, first post and new to BMW. Bought a 2003 325xi with 120K on it. Just put some new Firestrone Oval tires (see link to view tread pattern)
http://www.firestonetire.com/images/...de_oval_as.png

Here is the strange deal:

At highway speeds the car seems to 'float' around on the interstate. It's not an allignment issue for I had that done and it tracks wonderfully.
It just seems like I can't keep it still on the road when I get it above 70.
Should I be blaming the tires or do I have suspension parts that need replaced?_a_

VP 12-08-2012 03:25 AM

When I was a professional technician, many many years ago, we called that characteristic "Road Crazy". Maybe they still do, don't know. In rural areas where I worked, it was often an alignment issue. Old farm roads, people driving out into fields, etc. In more urban areas we saw less of that kind of thing, and less "road crazy" complaints. However, the cause was generally a caster issue, which helps with directional stability. Less positive caster, less directional stability. Since these cars don't really have much of a caster angle adjustment, not much can be done there. If there IS a caster issue, I would suspect some significant damage in the past which was not corrected the right way. With that said, I would strongly suspect the tires. I have had experiences with my Corvette and new vs. old tires make an incredible difference in Interstate driving. Some tires and some cars are more sensitive to the subtle (here in Illinois NOT so subtle) ruts in the outer lanes caused by heavy semi's in warm weather. And ... never have been a Firestone fan. LOL

Jimmys 530i 12-08-2012 03:59 AM

Quote:

Originally Posted by VP (Post 7237452)
When I was a professional technician, many many years ago, we called that characteristic "Road Crazy". Maybe they still do, don't know. In rural areas where I worked, it was often an alignment issue. Old farm roads, people driving out into fields, etc. In more urban areas we saw less of that kind of thing, and less "road crazy" complaints. However, the cause was generally a caster issue, which helps with directional stability. Less positive caster, less directional stability. Since these cars don't really have much of a caster angle adjustment, not much can be done there. If there IS a caster issue, I would suspect some significant damage in the past which was not corrected the right way. With that said, I would strongly suspect the tires. I have had experiences with my Corvette and new vs. old tires make an incredible difference in Interstate driving. Some tires and some cars are more sensitive to the subtle (here in Illinois NOT so subtle) ruts in the outer lanes caused by heavy semi's in warm weather. And ... never have been a Firestone fan. LOL

This. I had a big difference between the Bridgestone Potenzas that I have now and the Goodyears that came off.

Fast Bob 12-08-2012 10:07 AM

Had a similar sensation with a set of Blizzak MZ-01s....I referred to them as "big greasy donuts", that`s pretty much what they felt like. Anything over 70 mph imparted a VERY "nervous" feeling to the suspension, as if complete loss of control was imminent and you were about to slide right off the road. They never got any better with wear, so I replaced them with Dunlop Wintersport M3s, which were the complete opposite of the Blizzaks. The M3s do everything right, and are rock-steady at highway speeds, even at triple-digits....

Siskin 12-08-2012 11:07 AM

First off, welcome to the 'fest.

Second, I know the feeling you're talking about. I have a 2004 325xi and I encountered this on my way to North Carolina a few months back. Before you go and replace your tires, double check that they're all running the same pressure. If they're not, your AWD will constantly try to correct the imbalance and, I think, give the car a feeling that you're not really in control.

Next, shut your traction control all the way off (hold the button for 5+ seconds), get up to 70, and see if it pulls one way or the other. Again, sometimes the systems in this car have a way of masking simple problems. Well, not mask them, really, they just present differently.

scarede46er 12-08-2012 09:31 PM

It's your control arm bushings I bet. Cheap replacement and your problem should go away.

cwsqbm 12-09-2012 05:27 AM

Its obviously the tires - they're supposed to be circles, not Ovals. :)

Control arms are my first thought after that.


All times are GMT -7. The time now is 01:35 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
© 2001-2011 performanceIX, Inc. All Rights Reserved .: guidelines .:. privacy .:. terms