Suspension Guru question

[JayG]

I noticed that my Boxster has a slight drift to the right on the freeway. I would not call it necessarily pulling, but it does not track straight.

I have tried it on several different roads and in different lanes to eliminate any road banking or crowning.

I recently had a alignment done and the castor is slightly different,7.9 vs 8.0
Camber is matched on each side and no toe in the front and a touch in the back. Camber is maxed front and rear, -.5 in the front and -1.6 in the back

Any ideas how to correct the drift?

[jdraupp]

Usually caused by bad tie rod ends or drop links. Cheap and easy fix.

[JayG]

Originally Posted by jdraupp

Usually caused by bad tie rod ends or drop links. Cheap and easy fix.

Do you know the part numbers for an 04 S?

[johnsjmc]

Before replacing suspension parts Try swapping front tires side to side. Even if running a directional tread ,a temporary move will confirm if the drift is tire related or not.

[JayG]

I was also thinking of putting on my spare 18's on the front that some fairly worn Hankook V12s for a test. I currently have 17" with very new (<1k mi) Star Specs on the car. Haven't used the the 18's for a while and the car didi track straight with them and no vibration before.

There is also a vibration in the front and steering wheel on most roads starting around 80 mph
On smooth asphalt it is less pronounced, but still there. Didn't notice the vibration at the track a week or so ago

I'm not against replacing some suspension parts as I do have over 77k on the original ones

[JayG]

UPDATE

I swapped out a different front wheels/tires and I it still drifts to the right and still had a vibration starting around 80 mph

Took a good look at the drop links and there is no play and the rubber boots look perfect

[jb92563]

Looks like you have eliminated the tires and rims from the equation.

That leaves the suspension and alignment.

If you are confident its not the alignment then something must have play, perhaps only apparent under higher loads.

Brake rotor is dragging? Got a stone jammed up in the rotor/disk?

Could the torsion bar be applying more pressure on one side vs the other.

Vibrations come from unbalanced rotating parts so if its not the tires then the drive shaft/CV joints may have some play?

[911monty]

Jay; I'm in the bad tie rod or worn/loose suspension camp. Front tires tend to spread decreasing toe at speed, if you had 0 deg toe when aligned then it's possible that you could have negative toe at speed.

[JayG]

What you said Monty makes sense

JB, no rotor drag. Ill have to check the CV and drive shaft, but the vibration is coming from the front in any case

The drop links are not a lot of $, easy to change, and won't change the alignment in replacing, so that may be the first thing I try

The right front tire looks like some odd wear
These tires have only 1800 miles on them. Of course, that included 1 AX and 2 track days (~180 track miles)
the right side of the tire is the outside

I may try to get a warranty adjustment for uneven tire wear

[911monty]

Jay; Looking at that picture you need to get the car on a rack. The feathered center tread indicates a definite toe problem. Check track rod (tie rod) and control arm for play. Not likely a drop link problem.

[JayG]

Originally Posted by 911monty

Jay; Looking at that picture you need to get the car on a rack. The feathered center tread indicates a definite toe problem. Check track rod (tie rod) and control arm for play. Not likely a drop link problem.

I have never done any suspension work before.
Can I put it up on stands and check it that way?
How do I check the tie rods and control arm for play?

[911monty]

Easy job. Just jack up one side first. Then see if you can get someone to grab the wheel front to rear and rock back and forth while you look for play. Pay special attention to the ball joint on the track rod and control arm ends. There should be no movement. If there is then see if you can determine where.

PS: for clarification leave opposite wheel on the ground. This will prevent movement through the steering rack.

[JayG]

Just had an alignment done
Toe was off on the front

Now have 0.03 total toe front and 0.10 rear
also camber went from -.9 LF -.4 to -.9/-.7 (maxed out)

I had them check the components for wear and they said all was good

Still have a vibration starting at 80 MPH. Gonna have the balance checked
Also still have a drift to the right, Castor is 8.0 LF and 7.6 rt. Looks like the only way to fix that is the Wishbone Adjustable With Eccentric Screw and it is ~$450 rather than $100

[jdraupp]

Originally Posted by JayG

Just had an alignment done
Toe was off on the front

Now have 0.03 total toe front and 0.10 rear
also camber went from -.9 LF -.4 to -.9/-.7 (maxed out)

I had them check the components for wear and they said all was good

Still have a vibration starting at 80 MPH. Gonna have the balance checked
Also still have a drift to the right, Castor is 8.0 LF and 7.6 rt. Looks like the only way to fix that is the Wishbone Adjustable With Eccentric Screw and it is ~$450 rather than $100

It's possible that the wheel weights that assist in tire balance have come off. You could tryou getting your tires rebalanced. How old are your tires?

[JayG]

Originally Posted by jdraupp

It's possible that the wheel weights that assist in tire balance have come off. You could try getting your tires rebalanced. How old are your tires?

2 months 1800 miles
Planning on a rebalance this week

[nicecar]

I had the same problem which 99% of vibration gone after a road force balance ( simulates weight of the car when balancing).The shop I took it too said road force balancing equipment used on the website. I can tell you that after 95k I have replaced the entire front suspension chasing rattles, drifting, twitchy steering as well as vibration. Good luck!

[JayG]

The shop I use does road force balance

I bought the tires from Tirerack and one of the local Firestone shops is on their list of installers and they charged me $63 for mounting, balancing (roadforce) and valve stems

[jdraupp]

Originally Posted by JayG

2 months 1800 miles
Planning on a rebalance this week

Hmm, then I'm not sure. Could be wheel bearings?

[JayG]

Don't think it is wheel bearings
'They make no noise and I have given the tires some good tugs off the ground and no movement.

[Racer Boy]

The caster is pretty close, but that can definitely cause a pull to one side. The side with lest caster is usually the side the car will pull to, which is the case with your car. The more performance oriented the tire (stiffer sidewalls), the more you will notice any alignment issues.

Where did you have the car aligned? Was it a specialty alignment place (does high performance alignments, etc. Not a regular tire store like Firestone or Midas)?