Alignment problems 996 Targa

[Porsche Club]

I continue to have alignment problems with my Targa and going through
rear tires every 4,000 miles. Undue tread wear on the inside of the
tires.

Suggestions on where to go to have this looked at. The dealer and
Burt Brothers in Park City have done previous four wheel alignments to
no avail.

Thanks,

Dave

[jgre...@skyviewmail.com]

My 928 is similar, I have the tires dismounted and rotated side to side to
extend the wear

[Stu Hamilton]

There are a couple things that could be a problem.

First, the type of tire. While most tires will get 10,000-12,000 miles on
the rear of the later 911s (1995 and newer - with the LSA rear subframe) -
some brands are known to get MUCH less. If you are using Pirelli P-Zero's,
that is the problem - I think 4,000 is about average. Consider a switch to
something else (Bridgestone, Michelin - check the Tire Rack reviews).

Second, the LSA subframe is very complex. If it has ever been damaged, it
can be hard to get right again. If you can, get the car up on a lift, and
inspect all of the control arms (5 on each side), and compare them
side-to-side. Pay particular attention to bushings, as any worn/damaged
bushing may allow enough play so that it appears normal on the alignment
rack, but gives you too much toe (out) on the road. I assume if you have
been to the dealer, they used a true 4-wheel alignment machine - that is
critical.

If you have had it aligned twice, I imagine that the camber was checked. It
may have too much camber (top of the wheels leaning in). This situation
could be aggravated if the car has been lowered. Taking some out would help
the tire wear, but would be at the expense of cornering performance.

If your tires are symmetrical, you could also swap them left to right. That
won't help you fix the problem, but will make your tires last longer.

Stu Hamilton

[Darrell Troester]

Hillside Tires does a competition alignment and may be able to help diagnose
if you really have a problem.

Stu makes some very good points and is right on. There are a number of
brands of tires that will only give you 4,000 to 5,000 miles on the rear of
a 911.

Darrell

[David Dymaxion]

Another thought is to check your differential's limited slip. There is a spec for how much lockup you are supposed to get. If your diff is locking too much the car might be spinning the inside rear wheel more than you realize.

The other thought is if you corner harder it'll even the wear out somewhat. :)

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From: Porsche Club <DP...@allwest.net>
To: IRPCA <IR...@googlegroups.com>
Sent: Saturday, June 27, 2009 10:20:15 AM

Subject: Alignment problems 996 Targa