My problem is that it's like thats what's happening, but with no movement in the steering wheel. That's what makes it scary.

Newest diagnosis: bad rear wheel bearing.

 

^^^
Absolutely correct. Camber has a significant impact on the every day handling of a 911. Even more so when you factor in worn tires. It can make the car ""dart" and follow ruts and pavement changes....

 

i had my 993 lowered after installing performance springs. no issue whatsoever.

 

Even with no feedback in the steering wheel?

 

Front toe is my guess

 

-1.5 to -2 degrees camber is going to be less than noticeable when driving a car. This is the typical range of camber on just about most manufacturer specs. The rear of X5 BMW call for almost -4 degrees camber... and I'm pretty positive they don't dart all over the road.

You should be checking ball joints, double checking alignment, and any bushings or anything else suspension related that might be worn out that is causing additional play.

regardless, your car is never going to drive 100% straight if you're not holding onto the wheel while driving over cracks or undulations. What you're experiencing isn't bumpsteer at all.

 

The sheet I have from the last alignment says the specified range for front toe is 17-25. Should I ignore that?

 

I'm not sure I'm explaining this well. I hold the wheel perfectly straight and the car darts from one side of the lane to the other with no input from me. The wheel never moves, and it's not just drifting bc it's quick and it goes both ways.

 

I would suggest staying within the specified range, but there are obviously ways you can change it to "help" when primarily using the car for highway miles, or benefit someone who is using the car for track.

Having an overly aggressive alignment will make the car very darty and feel less stable, but could improve the turn-in on a track, which is desired by some.

A factory alignment will usually be pretty conservative with toe settings. Unless you're sure your suspension is 100% on par, and you're still not happy, I wouldn't try and deviate from them.

If you have a capable and knowledgeable shop, tell them your intentions of the car and they should know how to setup the car on the alignment rack to "help" meet your expectations.


*Also, I misread your initial alignment specs thinking you had toe out, so that's why I edited my previous post... just about at the end of my 12 hour work day -_-

 

If the car is darting left and right and you are not moving the steering wheel and you are getting zero feedback through the steering wheel I would suggest you stop driving the car until you get this sorted out. Having tires track irregularities in pavement is normal now and then when the tread pattern and the pavement sort of hook up...but that is more drifting than darting.

 

There are also certain tires that tend to "wander" or "hunt" more than others depending on the surface. We have some sections of grooved asphalt on the freeway and with certain tires it almost feels like you're driving on ice. Does it do the same thing on all types of roads?

 

Our roads don't really seem grooved, but yes it does do the same thing on all the highways here.

 

Problem solved. Left rear wheel bearing fixed this issue. Also cleared up some vibration I had in the steering wheel.

 

fantastic news

 

The news is fantastic, paying the bill was not!