C4S Rear Toe Confusion

I searched but couldnt find anything that described my exact problem so apologies if this is already covered. My problem started when I recently went to get an alignment at my local indy who has done 4 previous alignment, each turning out successful and on the same machine. Brief history below: 2017 128K Miles - Replaced rear main and fwd control arms (Meyle) and had an alignment done. - All within factory spec for street. - No suspension related changes since this alignment 2019 138K Miles - Rear passenger side toe is 1.6 deg out of range. - Drivers side is fine - Noted worn rubber bushing on toe control arm, replaced arm with OEM (Meyle) - Rear passenger alignment is now better but still 1.3 deg out of spec i.e. front of tire is pointing too far inward. - Adjustment bolt is at maximum. - Adjustment plates on bolt are not deemed worn. - Pressure with a long bar did not move arm enough to resolve discrepancy. I'm really trying to understand how it could still be out given the one part that affects this has just been replace with a brand new part. So my questions are 1) Has anyone come across a similar issue ? 2) Is there something else that could be worn that I may not be considering ? (there was an aluminum spacer that inserted into the hub but the fitment shows no wear when assembled) I'm really scratching my head here and would like to figure out a cause before I am forced to buy adjustable rear toe links for $400+. Thanks for any input

Does this car have lowering springs? What are the camber readings in the rear?

Car is on stock suspension. As we did not finalize the alignment this go round I didnt get a final print out of the settings. However I do know its a very neutral setting as to prevent excess wear on the inner portion of the tire. Car is not tracked

Maybe the toe bar is bent. My pass side was when i got my car but it was hard to see. If thats not it i would remove every suspension part one by one to inspec. Im guessing u have a bad bushing somewhere.

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That was what I thought with the old one in there but having replaced that I think its a low probability. If there is a specific bushing to take a look at let me know and I'll check it out

I would start with this one and go from there. There is also a bushing in the lower control arm that this bolts to. Not sure if anyone of the individual parts can cause your issue but all the rubber on your car is old. U may just be do for a suspension refresh or upgrade.

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Jepper, Appreciate the input, however those along with the main control arms were replaced right before the previous alignment was done. Follow up check revealed they are still tight.

Only other thing in there is the upper dog bones. Not sure if they affect toe but i guess they can.

I agree, thats about the only option left. I'll take a look at them this week and see how they check out. Thanks for the input

Just an update, I have checked out the top links. Nothing appears to be too worn out (cracked or deformed bushings) that would be throwing the toe out. I did bring it to the local Porsche dealer on Friday. Their assesment was that the replacement arm was slightly longer and that was causing the issue. This would make sense however upon removal of the new arm, I placed a bolt through it and the old one and they are identical. So as I see it my options are: 1) The indy shops alignment tool was mis-calibrated and there is not actual issue on the car. To prove this I would need a new alignment at the dealership to compare ~$300 2) Both alignments could come out the same, in which case I will need new adjustable arms such as Tarrett Engineering for approx $400 + a an alignment for the new parts. - given that I may want to do a suspension upgrade at some point and lower it, this may be a requirement anyways so maybe it makes sense to do this now and have the parts already installed Updates to follow as they develop

I always wonder about the calibration thing too. It would be interesting (although $$) to have another alignment done by someone else. As far as adjustable arms go, if you are considering lowering, I wouldn't replace either the toe arm or the upper control arms with non-adjustable one until I got the lowering completed. I lowered mine on Bilstein B8s and H&R lowering springs and need adjustable upper control arms to get camber into spec. This doesn't seem to be an issue for all, but it seems to be on my car.

This was not visible until I removed it. Lower track bar.

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Thanks for the input guys. After further deliberation I think the best option would be to go with the adjustable Tarrett control arms. I am looking at your exact suspension set up down the road and this would be a proactive step to that. The part that still bothers me about the alignment calibration itself could be solved by setting the adjustable arms to the exact length of the stock arm and getting a 2nd opinion. This would allow for me to remove that variable AND compensate should it need that extra range of adjustment. The only negative part of this equation would be that I have an essentially brand new arm that I would have no use for, but maybe that could be sold and recoup some cost

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IMO you should determine why the toe is off to begin with before installing adjustable toe links. if your new arm is identical to the prior unit, then something else is not right - either a poor alignment, or the eccentric is 180 degrees out, or something else like 808Bill shows. Installing new adjustable toe arms will not correct the original problem. I once had an E46 M3 alignment done at a local indy shop; the rear toe was so far off the new tires wore out in less than 10,000 miles, and the toe was maxed at extreme toe in one side, and toe out the other side. Owner wouldn't fess up to the poor alignment Weird; neither my 996 or 986 required new lower control arms for camber when I lowered them; only the toe arms had to be replaced

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What's weirder is that my toe came into spec with stock toe links. Again, I question the calibration of the alignment machine in my case too.

Since I have the car up on stands anyways I decided to remove the upper links for inspection. The bushings are not torn or ripped but there are some radial cracks and some obvious compression, especially on the fwd arm. As far as I can tell these are all original with 139K on them. Lifting the assembly, the front arm does seem to have definite input on the toe angle and given the state of the bushings could be what's throwing things out. To be safe I ordered 4 new arms (might as well do both sides). This is still cheaper ($256 V $400+) than the adjustable links and is the more "correct" approach IMO where as the adjustable links would have just been allowing compensation for the wear in the upper arms. I should have those in next week and will follow up on the install. Of note, I confirmed that the dealer part #997-331-045-04 for the lower rear toe control arm is the same as is listed on Pelican. So while there might be the slightest variation in the length of the new v old part, it is likely the dealer supplied part would be the exact same.

Its done. Dealership was able to align to factory specs. While they did not attempt an alignment with the old upper control arms, given the condition of the bushings, I suspect they are having a negative impact under load. So the take away is, if your alignment is out of range make sure to check on the top links as well before going the adjustable route. Hope this helps someone in the future

Glad it got solved.

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Me too, thanks for all the input and suggestions through the process

- Adjustment bolt is at maximum. Shouldn't be normally - Adjustment plates on bolt are not deemed worn. Did someone verify, both, Reason I ask is this bolt is very susceptible to working loose as it uses special tool Dog bone socket ) to tighten, adjust. Mine did on Driver side, 2.5 degree if not mistaken

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Fixed!