Squirrelly rear end in rain - new tires, new wheel bearing

[renzop]

What size front and rear tires do you have ? Incorrect size stagger can cause odd behaviors. What brand are the front tires? I would look at rear toe. Good luck!

[joshua6060]

Michelins on the front, couldn't afford to match the tires because I knew I was going to take a hit on regular maintenance and a few repairs over the last 2 months now pushing $4,500 all together....

I was thinking that it was an alignment problem on the rear end also.....

[Topless]

Sounds like a pretty big tire mismatch. Just don't lift your right foot unless you are going in a straight line.

[Quickurt]

Likewise, big tire mismatch. I'm not big on mixing brands or even styles of the same brand.
It won't show in the dry unless you're really at the edge, but in the rain, every little imbalance is magnifyed a hundred times......

[joshua6060]

I recognize the difference in the tires but there is no way that should cause my rear end to get loose in the rain going 55mph in a straight line.

I'm leaning toward the alignment being off.....

Originally Posted by joshua6060

I recognize the difference in the tires but there is no way that should cause my rear end to get loose in the rain going 55mph in a straight line.

I'm leaning toward the alignment being off.....

Wrong on the first account.

Correct on the last account.

The combo of both is never good.

[CJ_Boxster]

Originally Posted by joshua6060

I recognize the difference in the tires but there is no way that should cause my rear end to get loose in the rain going 55mph in a straight line.

I'm leaning toward the alignment being off.....

A good way to tell if its your alignment's fault, in dry weather when you go over a bump in the road, with 1 or the other rear wheel, do you get a shimmy from the rear end of your car til both rear wheels have even weight loads on them/are flat on the ground again?

If so then your Toe isnt up to spec anymore, you'll need an alignment

[pk2]

Originally Posted by CJ_Boxster

... do you get a shimmy from the rear end of your car til both rear wheels have even weight loads on them/are flat on the ground again...If so then your Toe isnt up to spec anymore, you'll need an alignment

CJ,

Don't want to hijack this thread and I don't go around smoking my tires all the time but, is a symptom of poor alignment also wheel hop on heavy acceleration?

In less than ideal conditions, if I make any effort to smoke the tires, the back hops all over the place. It also does this a bit powering out of a turn to (my sign that pushed it to the it to the edge).

Regards, PK

[Sboxin]

IMHO of course, if you have checked the tire pressures and they are normal then the next logical step is to have the alignment reset to spec and the suspension parts checked for wear (the bushings). I would use a good Porsche Indy for this work -- the dealer will just say its the non-N rated tires.

We have Sumitomo HTR ZII on 02S and ran through a 2" downpour with no problem at 60MPH. IMHO, I would say its not the tires.

Take care,
Ed

[Quickurt]

Originally Posted by Sboxin

IMHO of course, if you have checked the tire pressures and they are normal then the next logical step is to have the alignment reset to spec and the suspension parts checked for wear (the bushings). I would use a good Porsche Indy for this work -- the dealer will just say its the non-N rated tires.

We have Sumitomo HTR ZII on 02S and ran through a 2" downpour with no problem at 60MPH. IMHO, I would say its not the tires.

Take care,
Ed

A 2" downpour in Phoenix???
Is that 2" of sweat?

[Topless]

Originally Posted by Quickurt

A 2" downpour in Phoenix???
Is that 2" of sweat?

Annual rainfall in Phoenix is about 8". What they don't tell you is that most of it comes in 4 days.

There is nothing wrong with Sumitomo tires, they just have very different grip characteristics than PS2's, hence the mismatch. Match the tires all around, get an alignment and have an experienced Porsche tech poke around your suspension to make sure everything is sound. Do this before the next rainstorm so you don't become graffiti on some offramp. A little preventative maintenance is usually a lot less expensive than a hospital stay.