GT3 control arms

[geoff]

I know people swap out the stock control arms for the GT3 ones to get more negative camber.  I have a squeak from my front suspension I'm trying to diagnose, figuring it might be the lower control arms based on car mileage (64K miles, '01, ROW M030).  I'm not looking for more negative camber.  Besides being able to add shims which gives more negative camber and slightly wider track, do the GT3 control arms with rubber bushings hold up any better than the stock control arms?  I couldn't find anything about this by searching here and elsewhere.  Is the rubber any stiffer on the GT3, or do the GT3 ones just give you the ability to add shims?  It would be nice not to have to replace entire parts in the future just because the rubber bushing gets old.  (I don't want to spend the big bucks for the monoball pieces at this point.)

[savowood]

If you don't need the camber, you could simply get the bushings I think.  However, if you check at Suncoast, they have the GT3 control arms for _less_ than the standard Boxster ones.  At least they did a few months ago when I was looking into it.  You may want to give them a call.

-Michael

[geoff]

Michael,

Thanks for the info.  I'll check with Suncoast as well as Sunset

Do you know if the GT3 rubber bushings are the same as the stock ones, or do they hold up any better.  I didn't think Porsche sold replacement bushings for the control arms

[Lightning]

I don't think Porsche sells the lower control arm bushings separately. The only replacements I have seen are aftermarket monoball kits, which will probably increase suspension noise getting transmitted into the car (and they are kind of expensive; almost as much as a set of GT3 control arms ).

Control arms (either stock or GT3) are not cheap, so you may want to jack up the car and do some poking/shaking to find out what the problem is first. Really check the lower control arms to see if it's really the bushings. Might be a loose control arm bolt, loose strut tower bolt, bad strut, bad upper spring bearing, or even a cranky wheel bearing. If it is a bushing, you can take a chance (and save some money) and buy a used stock arm on eBay. Guys doing Boxster Spec conversions are selling them all the time.

Having said all that, if you're going to autocross or track a Boxster, I can wholeheartedly endorse the GT3 control arms, as the ability to get more front camber (and caster, if you want it) will allow you to optimize the camber setup for whatever tire you're using and dial out ALL of the understeer the car has. Without really compromising streetability. (Sunset is usually a pretty good place to buy them). Unfortunately, I don't know if the inner bushings are any more durable than the ones on the stock control arms, as they are both rubber.

[geoff]

I'm still trying to diagnose the source of the squeak.  I went to the dealer last week, and the mechanic tightened the sway bar bushings and drop link bolts, then squirted some magic Wurth lubricant on the lower control arms.  Between rain and business trips, I haven't had a chance to drive the car to see if the squeak is still there or not.  If that clears up the problem, at least I've somewhat isolated the source, and the next time the problem surfaces can re-lube the control arm bushings and see if that again fixes it.  Otherwise, I'll look at another possible source for the squeak.

I didn't think Porsche made an OEM replacement rubber bushing.  The only aftermarket ones I've seen are the Elephant Racing ones at http://elephantracing.com/suspension/rubberbushings/996rubberbushings.htm but haven't seen any reports of people using them.  I'm not sure how much time is involved in replacing just the rubber bushings, so maybe the cost savings compared to the additional labor involved won't much of a saving.

At some point, I'd like to autocross my car, so I'll probably go with the GT3 control arms if I have to replace them.  I'm just trying to get smart in advance so I can make an intelligent decision if/when I have to replace the arms.

[Gary Samad]

If you plan to autocross your car, be sure to think about what class you want to compete in, since changing the control arms will definitely take you out of "stock", which will make you uncompetitive unless you start spending a whole lot more money on the car.

  Gary

[catman]

Both the split GT3 and regular lower arms have the same rubber bushing...

[geoff]

Sorry about not posting sooner, but I wanted to make sure the problem was actually resolved.  I spent more time at the dealer, and the head mechanic went for a second, extended joy ride with me to try to figure out the problem.  We drove up some of the canyons by the dealership, and the mechanic finally heard the problem.  We eventually found an intersection where we could reliably reproduce the problem.  It turned out to be the hood latch mechanism and not a worn suspension component after all.  When we got back from the joy ride test drive, he adjusted the front hood latch and rubber feet.  The hood is harder to close, but the squeaking noise is gone.

The only downside is I have no justification whatsoever now for upgrading to the GT3 lower control arms

According to comments I received on the (now defunct) Boxster spec racing board, the GT3 lower control arm bushings are more firm than the stock ones.  I have no way to confirm or disprove the comment, just passing it on.