[SILVY968]

I have had my 1995 968 since October of 2004. When I got it it needed an alignment.

I got an alignment and 4 new Dunlop 901's. I have a rumble when I drive between 58 and 62 MPH.

The alignment has been checked by 2 shops, I have had the bearings, cv joints, calipers and everything else checked. All are OK.

I have has the wheels balanced many times and still the problem.

Rear shocks are new Koni's. Front shocks replaced 12K miles before I got her.

I am running 18" turbo twist wheels, that have been straightened. Tires are 265/35ZR18 93W in the rear and 225/40ZR18 88W in front.

The cold pressure is 36#.

On my daily drive I run at these speeds all of the time.

Dunlop has replaced the rear tires, which improved it a little, but it is still there.



Anyone ever had this problem, or have an idea as to what it could be?



PS The ride on these 901's lets you feel every minor imperfection and they do pull all over the road.

I am thinking of getting ES100's when these wear out.

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[sasilverbullet]

Sounds like a tire is bad...



Find a shop with a Hunter Road Force balance machine. Most Porsche dealers have them now. They'll be able to find the bad tire in a heartbeat!

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[bob blackwell]

Brian, the "pulling all over the road" is most likely the result of those wider wheels and tires. I have 18 inch wheels installed too and have the same "tram lining" or wandering too. I noticed the same thing when I was running 8x16 inch wheels all around. the wider tread seems to make the car less likely to want to go straight. I don't think different tires will make much difference. Good luck, Bob Blackwell.

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[ds968]

[quote name='sasilverbullet' date='Jun 17 2005, 06:10 AM']Sounds like a tire is bad...

Find a shop with a Hunter Road Force balance machine.

[right][post="5993"]<{POST_SNAPBACK}>[/post][/right][/quote]



Had the same symptoms on my other car ( also around 60 mph, give or take a couple of miles ..) aligned and balanced several times with no results... and it was a bad tire - and it was a brand new tire, just had a manufacturing defect not detectable to the eye, but easily discovered by the road force balance mechanism.



But if subsequent to the test all the tires check out ok, I have no clue..

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[SILVY968]

[quote name='ds968' date='Jun 17 2005, 07:33 AM']Had the same symptoms on my other car ( also around 60 mph, give or take a couple of miles ..)  aligned and balanced several times with no results... and it was a bad tire - and it was a brand new tire, just had a manufacturing defect not detectable to the eye, but easily discovered by  the road force balance mechanism.



But if subsequent to the test all the tires check out ok, I have no clue..

[right][post="5996"]<{POST_SNAPBACK}>[/post][/right][/quote]

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[SILVY968]

I'll press Goodyear for a new pair of fronts and see if the problem goes away.

Replacing both rears did not change the problem.



I'll locate the Hunter machine and give it a try.

I appreciate all of the info.



Looks like top down weather this weekend, can't wait.

Summer in Seattle with a cab feels great!



I'll let you all know if the new fronts worked.

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[SILVY968]

Well, I got a brand new passenger front tire mounted and balanced today.

Rumble all gone. Joey at Fordahl Motorsports was right on the money.

Michael and Dan...thanks for the right answer as well.

If any of you ever have a problem with a Goodyear or Dunlop tire email your complaint to Goodyear on the web site. They responded the next day and took care of the problem at no cost. The tires has over 6 months of wear on them and the swapped them for new without a prorated adjustment cost.

Brian

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