E46 M3 BAD tramlining. Need help.

[FBloggs]

Perhaps you could do a squirrel test.
place a traffic cone in the middle of an empty parking lot.
Leave the DSC on.
Approach the cone at 20 mph dead on.
Swerve at the last instant, being prepared to catch the tail.
perform the test several times.
Think about how the chassis behaved.
Did the chassis behave as a single unit?
Or was there a lag between the action of the front end and the response of the rear end?

Because the chassis should behave as a single unit if all the suspension components are in good shape.

Think about what the front end did.
Think about what the rear end did.

Did the front end have good recovery, and stabilise to straight promptly?
Was the rear end "late"? And sloppy?

Are you using poly front swaybar bushings?

[thetypicalm3guy]

Perhaps you could do a squirrel test.
place a traffic cone in the middle of an empty parking lot.
Leave the DSC on.
Approach the cone at 20 mph dead on.
Swerve at the last instant, being prepared to catch the tail.
perform the test several times.
Think about how the chassis behaved.
Did the chassis behave as a single unit?
Or was there a lag between the action of the front end and the response of the rear end?

Because the chassis should behave as a single unit if all the suspension components are in good shape.

Think about what the front end did.
Think about what the rear end did.

Did the front end have good recovery, and stabilise to straight promptly?
Was the rear end "late"? And sloppy?

Are you using poly front swaybar bushings?

I dont even need to do the test, I already feel like the body and the steering do not match each other. This leads me to think its bushing related. No, on OEM sway bar bushings. The front end feels "late" rear end, from what i can tell, seems solid.

[FBloggs]

So you have poly for the front swaybar bushings?
Are they powerflex?

Is the front end late to react to the initial steering input?
Or is it late on recovery?

[BlueBimmers]

Jumping in late I know. Good article in May/June derBayerische about alignments. Article stressed that a little toe out in front helps turn it, and a little toe in for the rear helps stability. Hope you figure this out.

[thetypicalm3guy]

So you have poly for the front swaybar bushings?
Are they powerflex?

Is the front end late to react to the initial steering input?
Or is it late on recovery?

No the sway bar bushings are OEM and original. No cracking I can see though. I would say late to initial steering and also late on recovery. The steering seems variable. Sometimes slightly left goes straight, sometimes straight goes straight, sometimes slightly right goes straight. Something has got to be loose.

[FBloggs]

No the sway bar bushings are OEM and original. No cracking I can see though. I would say late to initial steering and also late on recovery. The steering seems variable. Sometimes slightly left goes straight, sometimes straight goes straight, sometimes slightly right goes straight. Something has got to be loose.

Just to be clear, you're describing the steering feel here? Not the nose of the car?

If it was my car, I would now be looking at
1, whether the tierods are E46M3....not E46 vanilla.
2, The steering angle sensor.
3, The front wheel bearings( raise the front end, grab each wheel at 3 and 9 o' clock and push/pull in those directions).
If the bearings are bad enough to affect the steering, they should be howling by now.
4, power steering pump.
5 steering rack.
6, check that the new steering guibo is indexed correctly and clamping tightly.
The front end is pretty much refreshed.

Has the car been previously damaged in a front end collision?

[bmwfnatic]

Just to be clear, you're describing the steering feel here? Not the nose of the car?

If it was my car, I would now be looking at
1, whether the tierods are E46M3....not E46 vanilla.
2, The steering angle sensor.
3, The front wheel bearings( raise the front end, grab each wheel at 3 and 9 o' clock and push/pull in those directions).
If the bearings are bad enough to affect the steering, they should be howling by now.
4, power steering pump.
5 steering rack.
6, check that the new steering guibo is indexed correctly and clamping tightly.
The front end is pretty much refreshed.

Has the car been previously damaged in a front end collision?

Quick question, what does the steering angle sensor have to do with this?

[FBloggs]

In the mk60 cars, it talks to the dsc.

[bmwfnatic]

In the mk60 cars, it talks to the dsc.

Yes, but how would that be related to tramlining?

[FBloggs]

I understand that The dsc uses input from steering angle sensor to function correctly. If the steering angle sensor is relaying faulty info, there may be unwanted activity from the dsc,
Having said that, I'm going by the OPs perspective/description of the cars behavior..

I know from my example, tramlining was only one of several drivability issues that the car had.
Typically tramlining was the term used to describe the front tires following ruts or road camber.
It is an irritating trait, but not dramatic.
The rear axle can also exhibit tramlining if components are worn.

There was a comment by the OP that the car behaved as if he was driving drunk.
To me this suggests that the car has no straightline stability...problems at both ends, if constant steering adjustments have to be made.

[Arith2]

Are you sure it's not an improper install of suspension? For example, if you tightened the bolts on the front control arms with the suspension unloaded it would drive weird, you need a preload when tightening those bolts.

I'm really wondering if this is the issue. Even hand tightened bushings will not relax unless fully slackened, loaded, and then tightened. A jack pushing up on the suspension will not do the job properly.

[thetypicalm3guy]

I'm really wondering if this is the issue. Even hand tightened bushings will not relax unless fully slackened, loaded, and then tightened. A jack pushing up on the suspension will not do the job properly.

You know what. This could be it. I definitely torqued down the control arms and tie rods on jack stands. How am I supposed to torque them down on the ground though?

[bmwfnatic]

You know what. This could be it. I definitely torqued down the control arms and tie rods on jack stands. How am I supposed to torque them down on the ground though?

Check if there is a DIY Garage nearby, and they have a 4 post lift, makes for easy work.

Alternatively, drive the car onto ramps, then jack up the rear and put ramps underneath as well, lower it.
Push down on all 4 corners and let it settle to ride height (not ideal when having just jacked it up, but it will have to do).
Then loosen the bolt until the bushing relaxes and torque it down.

[Arith2]

Check if there is a DIY Garage nearby, and they have a 4 post lift, makes for easy work.

Alternatively, drive the car onto ramps, then jack up the rear and put ramps underneath as well, lower it.
Push down on all 4 corners and let it settle to ride height (not ideal when having just jacked it up, but it will have to do).
Then loosen the bolt until the bushing relaxes and torque it down.

The four ramps thing is doable. The only issue will be settling the suspension but it's not that significant. Just making sure all four wheels are holding full weight is the most important part. I have an alignment rack to do it on but in the garage that's what I did. Shock bushings can be done without lifting the car but everything else with need a lift most likely.

[thetypicalm3guy]

Damn, who would have thought. Okay, I will do this. Loosen all bushings and arms that I installed in the air, let vehicle settle down with all weight on floor, then torque down to required spec. Sound good?