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Discussion Starter #1
Hi all,

This has been quite the month for the front end of my Cayman. Back in October, my local indie shop noted "minor play in the front lower control arm bushings," and advised replacement before doing any "track or spirited driving." I've since noticed a slowly increasing amount of vibration in the steering wheel at highway speeds. While it isn't extreme (I'd give it a 4/10), it is definitely present at speeds greater than 55mph. I'm not hearing any creaking from the suspension, nor is there any vibration at low speeds.

After some forum research, it sounds like these cars are extremely sensitive to wheel and tire balance. The car has been into the shop several times for unrelated issues, and they've re-examined the front LCAs on each visit. However, they haven't mentioned any additional degradation of those components (i.e. nothing warranting immediate replacement) on any of those subsequent visits. The car has been driven somewhere between 1000-1500 miles between October and this month.

Additionally, my front rotors appear to be in need of replacement in the near future. They seem to rust excessively, and appear to be mildly warped as well (some brake pedal pulsing on heavier deceleration, though this is often as a result of rust being scrubbed off of the rotors by the pads). Finally, my tires are about due for replacement.

It seems to me like it may be difficult to pinpoint which of these issues (if any) is causing the steering wheel vibration, as they all seem to be potential contributors. Where would you start? My initial thought was to begin with tires as those are needed regardless, and then proceed to the brakes, which I can likely replace myself. I'd likely take the car to my indie shop for the LCA replacement, as I'm not quite sure that I trust myself to sort that one out just yet.
 

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I'd start with cheapest first. Inspect your tires for abnormal wear patterns, if you don't see any that's a good sign that you probably don't have a significant suspension issue.

Second, have the tires rebalanced, or since you need to replace them anyway, go ahead and do that. The weights they have been using over the past half-dozen years or so do not stick very well. I lost and entire strip a couple weeks after purchasing new tires with the car just sitting in the garage. If the tires get good an hot with a spirited drive, you have a really good chance of throwing them. I have to put aluminum tape on my track wheels to keep the weights on.

Light brake rotor rust is not a big issue. I get it after washing, and it gets cleaned off with a few good applications of the brake pedal. I recommend you do an occasional brake pad bedding-in procedure to help mate the pads and brakes, especially if you just use it around town and don't really get on the brakes very often. This will also help reduce brake squealing.

Pay attention after you get new tires. If you still have issues, then troubleshoot further. Don't drive too long with a lingering issue to avoid trashing your new tires, but a few weeks of daily driving isn't likely to cause a problem..
 

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Discussion Starter #3
I appreciate the response! The tires have purportedly been on the car since 2016 and have not, to my knowledge, been rebalanced since then. As the problem has increased slowly over time, I can easily see how that could be the issue, especially given the lack of weight over the front end. I went ahead and took advantage of a Costco sale to get a new set, which will hopefully solve the issue.

As far as rotor rust goes, I'd categorize what I'm experiencing as moderate to heavy (6-8/10). The accumulation is sometimes enough (after a heavy rain, for example) to cause rhythmic scraping against (I assume) the pads even when the brakes are not being applied. I'd estimate the rear brakes typically have around half the rust accumulation of the fronts. I do have a receipt from the previous owner for new front rotors, which were apparently $50 each. I'm not sure if that might've been an industry discount, but that's far cheaper than what appears to be the average rate for individual CS rotors (318mm Zimmermans from FCP Euro, specifically). Could I just be experiencing the effects of cheap brakes? Regardless, I'll try bedding the brakes in. Unfortunately I live in a fairly populous city, so good driving roads and heavy braking opportunities are pretty rare.

Glad to hear it. This is my first set of tires (first Porsche, first used car, first car I've worked on, etc.), so I definitely was concerned about doing some damage. Ideally I'd like to get the LCAs replaced ASAP, and then just do one alignment. My usual indie shop charges somewhere around $300 for the procedure, so I'd rather just do it once.
 

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Discussion Starter #4
Edit: internet issue and webpage-refresh caused an identical repost of the first message.
 

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$50 rotors? Never seen any that cheap. I'm currently running OEM in the front and Zimmerman in the rear from FCPE on my 981BS. I daily drive mine, so it gets a lot of weather. They both seem to rust about the same - which is a considerable amount when it rains.
 

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since your indy has checked it and the LCA is already identified as having an issue I would probably start with that. From your description it also sounds like its gradually getting worse which points it to being wear related.

old tires don't do this car justice and some fresh rubber may do it some good (depending on tire brand and age - mileage as well as calendar age).

rust on rotors should go away within a few brake cycles. any more and they must be really caked or something else is wrong.

actually it may be better to do all 3 as you can get a nice alignment and balancing done after the work. do budget for a few extras such as brake pads, more than 1 lower arm, other wear and tear items.

good luck.
 

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Discussion Starter #7
since your indy has checked it and the LCA is already identified as having an issue I would probably start with that. From your description it also sounds like its gradually getting worse which points it to being wear related.

old tires don't do this car justice and some fresh rubber may do it some good (depending on tire brand and age - mileage as well as calendar age).

rust on rotors should go away within a few brake cycles. any more and they must be really caked or something else is wrong.

actually it may be better to do all 3 as you can get a nice alignment and balancing done after the work. do budget for a few extras such as brake pads, more than 1 lower arm, other wear and tear items.

good luck.
After a few phone calls, I've managed to get it all sorted out. New tires are being fitted tomorrow (current ones are at least four years old, unknown mileage), and another indie shop is fitting new LCAs on Tuesday. They were kind enough to price match the ones I'd found online, so including the alignment, I'm looking at a bit under $1,200 in total. Seems like a pretty fair price to me?

I also went out and found a pretty abandoned stretch of road to do some repeated heavy braking on. Pedal feel is decent, though new brake fluid may be needed soon (the pedal is a little bit soft). No buffeting in the pedal, but plenty of shake in the steering wheel, including some audible clicking or knocking.

Assuming this takes care of the vibration, next up will be some new rotors and pads for the front. The rust is indeed eventually scrubbed off after about 15-20 minutes of typical city driving. The buildup is certainly more than what I've seen on any of my other previous cars, but perhaps that's as a result of these particular rotors? According to the receipts from the previous owner, they were $50 a piece, which strikes me as unusually cheap. Definitely will be replacing them in the near future. I'm also trying to source a GT3 shifter to eliminate both some shifter play, and a good bit of noise that appears to be emanating from the gear-shift assembly itself.
 

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Discussion Starter #8
$50 rotors? Never seen any that cheap. I'm currently running OEM in the front and Zimmerman in the rear from FCPE on my 981BS. I daily drive mine, so it gets a lot of weather. They both seem to rust about the same - which is a considerable amount when it rains.
Nor have I, so I feel like they could be a little suspect. How have you liked the Zimmerman rotors? Seems like they get generally positive reviews. I'll try and grab a picture of the rotors after the next rain–maybe mine aren't unusual at all.
 

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I'm also trying to source a GT3 shifter to eliminate both some shifter play, and a good bit of noise that appears to be emanating from the gear-shift assembly itself.
Numeric shifter and cables - no play, bolt-like action. And I am getting no gear noise through the shift cables.
 

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n163mv- You should ask lesmurray exactly how he avoided any transmission whine through the steel cables and follow his direction. I love my Numeric shifter/cable combination, as they really add to the 6 speed sensation, especially downshifting into 1st gear.
 

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Numeric shifter and cables - no play, bolt-like action. And I am getting no gear noise through the shift cables.
I've definitely heard great things about the numeric shifter! $700 is a big pill to swallow, though. Did that eliminate the gear noise? I've already got the cables, luckily! A pair of my friends had the OEM cables snap in their boxster just the other day, and are also upgrading.
 

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n163mv- You should ask lesmurray exactly how he avoided any transmission whine through the steel cables and follow his direction. I love my Numeric shifter/cable combination, as they really add to the 6 speed sensation, especially downshifting into 1st gear.
Is it worth the premium over the GT3 shifter? Mostly I'm looking to eliminate the noise and play, so if The numeric does it and the GT3 does not, it may be worth saving my money for.
 

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The Numeric shifter is like jewelry for your car. The thing is a work of art. In the middle setting it has a nice short throw that is solid. No play, no wiggle, just like a bolt-action rifle.

Oh, and you may want to ditch the factory shift knob for something a little more substantial. I bought a Black Forest Industries knob that weighs around 250 grams. I think the Carrera GT shifter would look super nice as well or the Turbo shifter. Basically, you want something with a little weight.

The cables are where you will get whine. My installer retained all the factory grommets coming through the firewall. It's a bit of a pain but worth the effort.
 

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I had similar issues on my 06 Boxster S and resolved them. I had play that I could feel both sides so installed new inner and outer tiers that were pretty bad.I changed the lower control arms myself but (Dam) they ended up being ok, perfect really after that better but still not perfect so I had all the tires Hunter road balanced and that solved it.Steering wheel dosent vibrate or shimmy side to side at any speed now, much nicer to drive car, especially fast,more control and confidence forsake. FYI I did try the usual type balance first with no change. The Hunter Road force balance was the ticket. Had to drive a few hrs to find a guy that had the machine but well worth it and no more expense that a regular balance. I had my rims checked also for bends as that can happen on the **** roads we have here. But mine were perfect.I have had a bad rim years ago on the front from a pot hole and it was terrible the shake in the car ,could feel it rite up thru the seat into my spine. Luckly found some used rims that were perfect .
 

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The Numeric shifter is like jewelry for your car. The thing is a work of art. In the middle setting it has a nice short throw that is solid. No play, no wiggle, just like a bolt-action rifle.

Oh, and you may want to ditch the factory shift knob for something a little more substantial. I bought a Black Forest Industries knob that weighs around 250 grams. I think the Carrera GT shifter would look super nice as well or the Turbo shifter. Basically, you want something with a little weight.

The cables are where you will get whine. My installer retained all the factory grommets coming through the firewall. It's a bit of a pain but worth the effort.
Sounds like a must-buy, especially considering it's only $200 more than the OEM GT3 shifter that I was considering. Which BFI knob did you pick up? I've been eyeing this Raceseng knob. I saw it in someone's youtube review, and I like the pseudo-OEM look. I agree though, a CGT style knob would be superb!

Ah, I see. The cables were installed by the previous owner of my car, so I'm not sure what their methodology was. But based on the noise, I'm assuming they didn't retain the grommets. I'm also getting some grinding/whining from the shifter console itself at times, so hopefully the Numeric shifter will eliminate that as well!
 

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I had similar issues on my 06 Boxster S and resolved them. I had play that I could feel both sides so installed new inner and outer tiers that were pretty bad.I changed the lower control arms myself but (Dam) they ended up being ok, perfect really after that better but still not perfect so I had all the tires Hunter road balanced and that solved it.Steering wheel dosent vibrate or shimmy side to side at any speed now, much nicer to drive car, especially fast,more control and confidence forsake. FYI I did try the usual type balance first with no change. The Hunter Road force balance was the ticket. Had to drive a few hrs to find a guy that had the machine but well worth it and no more expense that a regular balance. I had my rims checked also for bends as that can happen on the **** roads we have here. But mine were perfect.I have had a bad rim years ago on the front from a pot hole and it was terrible the shake in the car ,could feel it rite up thru the seat into my spine. Luckly found some used rims that were perfect .
Gotcha! I ended up getting a solid deal on the repair work at a local indie shop, who were also able to provide some insight into a couple other issues I've had as well. The steering wheel shake is largely gone now, but I still am experiencing some under heavier braking. The shop found that the tops of my struts had play in the mounts, and that's where they think the rest of the play is coming from. The prior owner replaced the strut mounts with track-oriented ones, which seem to be contributing to both the harsh ride I've experienced, and the play in the struts. OEM replacements to follow!
 
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