my left rear tyre shattered

[bohemia]

hello,

i'm an american living in the czech republic.

i just picked-up a 2002 996C2 on monday 29 december and yesterday i drove it to austria (about 200 miles away) on the autobahn. the car developed a vibration at about 130mph and i continued to accelarate to 175mph when it really vibrated. so 10-15 seconds after it developed noticable vibrations, i slowed down and not long after, my rear left tyre was shattered.

the car is currently fitted with winter tyres; 205/50/17 94V(front) and 225/45/17 94V(rear). after i changed the shattered tyre using the emergency replacement, the right rear tyre is now dragging. you could smell burning rubber everytime you stop, even if you drive for 5 to 10 miles at very low speed, around 40mph.

the car is still under warranty with porsche approved and i'm bringing it back on monday. i want to know what happened to the car before i speak to the mechanic. so my questions are as follows:

- what are possibilities for a car to develop a vibration (i could feel it on my cheek and teeth)?

- were the tyres not properly alligned and/or balanced? or is the car fitted with the wrong tyres?

- is it possible something broke in the rear of the car at such high speed?

on a separate issue:

- the car has a rattling noise when it goes over coble-stone road behind the back-seat. it sounds like a loose plastic part. what could it be?

- i have a 993C2 and i feel the 996C2 sways more in the front. is it the characteristic of 996? both cars are in factory specs.

thank you in advance for your help

[OCNYPORSCHE]

hello,

i'm an american living in the czech republic.

i just picked-up a 2002 996C2 on monday 29 december and yesterday i drove it to austria (about 200 miles away) on the autobahn. the car developed a vibration at about 130mph and i continued to accelarate to 175mph when it really vibrated. so 10-15 seconds after it developed noticable vibrations, i slowed down and not long after, my rear left tyre was shattered.

the car is currently fitted with winter tyres; 205/50/17 94V(front) and 225/45/17 94V(rear). after i changed the shattered tyre using the emergency replacement, the right rear tyre is now dragging. you could smell burning rubber everytime you stop, even if you drive for 5 to 10 miles at very low speed, around 40mph.

the car is still under warranty with porsche approved and i'm bringing it back on monday. i want to know what happened to the car before i speak to the mechanic. so my questions are as follows:

- what are possibilities for a car to develop a vibration (i could feel it on my cheek and teeth)?

- were the tyres not properly alligned and/or balanced? or is the car fitted with the wrong tyres?

- is it possible something broke in the rear of the car at such high speed?

on a separate issue:

- the car has a rattling noise when it goes over coble-stone road behind the back-seat. it sounds like a loose plastic part. what could it be?

- i have a 993C2 and i feel the 996C2 sways more in the front. is it the characteristic of 996? both cars are in factory specs.

thank you in advance for your help

You are very lucky, that you are OK. V rated tires are only good up to 149MPH. Tires are never to be driven past their rating. I do not think that Porsche allows V rated on 911s.

[win911]

I wasn't aware that the 996 came with 17 inch rims?

As for the vibration in high speed.. I'm guessing unbalanced tires.

Good Luck

[Foster]

:eek: I think my shorts would've been a total loss!

Glad you weren't hurt!

Do your wheels have spacers? How thick? Did you use them when you put on the spare?

Behind the back seats there are tubes attached to the underbody with plastic clips.

If the clips are broken the tubes may be hitting one another when you go over bumps.

There's also the plastic panels. The fasteners are plastic and break easily. The panel may be loose.

The only other thing I can think of is the transmission support brakets are loose. That would be bad. Have that looked at.

Edited January 4, 2009 by Foster

[perryinva]

So you felt a vibration at 130MPH on snow tires and then ACCELERATED to 170mph to what, make it go away? If the tire shatteed, (not the rim), then it's probably because you exceeded the speed rating of the tire. Had you checked air pressure before going triple digit? What kind of fool pushes SNOW tires to 130 mph??? Did you think speed ratings were merely suggestions? Second, if you put the spare on the rear then you didn't RTFM!! Spare ONLY goes on the front, it's written in about 5 different places. You have to move a front wheel to the rear, and put the spare up front, THEN you also have to disengage the PSM or traction control, as the difference in diameters will cause it to activate all the time and burn up. This post has to be a spoof....no one does this kind of stuff to a Porshe..

Edited February 1, 2009 by perryinva

[JeTexas]

Old tires, even if they have good tread, can get sort of rotten and fall apart at high speeds.

[White987S]

Amazing!

[KevinMac]

win911 If I am not mistaken the base were 17's and the option was for 18's.

bohemia It sounds as though the belts seperated and new tires are in order. You may want to opt for higher speed rated tires!

[magcuda]

it sounds to me that the tire had a slow leak/puncture and instead of slowing down to check out the tires, speed was increased and the side wall gave out. this gives the appearance that the tire "shattered".

it is hard to tell that you have a soft tire, even with the 17" wheels. harder when you go up in rim size since the side wall of the tire gets shorter.

[gofaster]

So you felt a vibration at 130MPH on snow tires and then ACCELERATED to 170mph to what, make it go away? If the tire shatteed, (not the rim), then it's probably because you exceeded the speed rating of the tire. Had you checked air pressure before going triple digit? What kind of fool pushes SNOW tires to 130 mph??? Did you think speed ratings were merely suggestions? Second, if you put the spare on the rear then you didn't RTFM!! Spare ONLY goes on the front, it's written in about 5 different places. You have to move a front wheel to the rear, and put the spare up front, THEN you also have to disengage the PSM or traction control, as the difference in diameters will cause it to activate all the time and burn up. This post has to be a spoof....no one does this kind of stuff to a Porshe..

Hey perryinva... your pretty hard on people.

Where did you learn to spell???

P-O-R-S-C-H-E not Porshe!!! What, are you an idiot???

[Loren]

So you felt a vibration at 130MPH on snow tires and then ACCELERATED to 170mph to what, make it go away? If the tire shatteed, (not the rim), then it's probably because you exceeded the speed rating of the tire. Had you checked air pressure before going triple digit? What kind of fool pushes SNOW tires to 130 mph??? Did you think speed ratings were merely suggestions? Second, if you put the spare on the rear then you didn't RTFM!! Spare ONLY goes on the front, it's written in about 5 different places. You have to move a front wheel to the rear, and put the spare up front, THEN you also have to disengage the PSM or traction control, as the difference in diameters will cause it to activate all the time and burn up. This post has to be a spoof....no one does this kind of stuff to a Porshe..

Hey perryinva... your pretty hard on people.

Where did you learn to spell???

P-O-R-S-C-H-E not Porshe!!! What, are you an idiot???

Please re-read the Board Rules/Guidelines that you agreed to when you registered here.

"Name calling or harassment of any kind directed towards another member or members will not be tolerated."

Back on topic folks.

[gofaster]

So you felt a vibration at 130MPH on snow tires and then ACCELERATED to 170mph to what, make it go away? If the tire shatteed, (not the rim), then it's probably because you exceeded the speed rating of the tire. Had you checked air pressure before going triple digit? What kind of fool pushes SNOW tires to 130 mph??? Did you think speed ratings were merely suggestions? Second, if you put the spare on the rear then you didn't RTFM!! Spare ONLY goes on the front, it's written in about 5 different places. You have to move a front wheel to the rear, and put the spare up front, THEN you also have to disengage the PSM or traction control, as the difference in diameters will cause it to activate all the time and burn up. This post has to be a spoof....no one does this kind of stuff to a Porshe..

Hey perryinva... your pretty hard on people.

Where did you learn to spell???

P-O-R-S-C-H-E not Porshe!!! What, are you an idiot???

Please re-read the Board Rules/Guidelines that you agreed to when you registered here.

"Name calling or harassment of any kind directed towards another member or members will not be tolerated."

Back on topic folks.

Your right... I apologize.

[bradmay]

So you felt a vibration at 130MPH on snow tires and then ACCELERATED to 170mph to what, make it go away? If the tire shatteed, (not the rim), then it's probably because you exceeded the speed rating of the tire. Had you checked air pressure before going triple digit? What kind of fool pushes SNOW tires to 130 mph??? Did you think speed ratings were merely suggestions? Second, if you put the spare on the rear then you didn't RTFM!! Spare ONLY goes on the front, it's written in about 5 different places. You have to move a front wheel to the rear, and put the spare up front, THEN you also have to disengage the PSM or traction control, as the difference in diameters will cause it to activate all the time and burn up. This post has to be a spoof....no one does this kind of stuff to a Porshe..

Hey perryinva... your pretty hard on people.

Where did you learn to spell???

P-O-R-S-C-H-E not Porshe!!! What, are you an idiot???

Please re-read the Board Rules/Guidelines that you agreed to when you registered here.

"Name calling or harassment of any kind directed towards another member or members will not be tolerated."

Back on topic folks.

Your right... I apologize.

I think the strong comments by perryinva were on target. He's the only person who offered this guy advice that may keep him from killing himself at high speed.