I was wondering if the sensors from the 17" is the same as the sensor on the 19" wheels. I am doing a swap today but before I do it, I just want to make sure it'll fit. thanks

nevermind.. it was just done and it works fine.
1 problem is that i changed the on board computer to 19 and summer tires. now it's saying that it's -4psi in the front. aren't the 19" wheels suppose to have 30psi in the front and 37psi in the rear?

Page five of your owner's manual is a good place to look.
"[b]Tire Pressures for Cold Tires[/B ]Summer tires and snow tires
Please observe the chapter “TPC TIRE PRESSURE MONITORING” on Page 103.
These tire pressures are valid only for Porsche approved tires.
For replacement tires it is imperative that you consult the Technical Data and Tires, Wheels
sections of this manual and follow the recommendations found there.
18 inch wheels front 29 psi (2.0 bar)
rear 36 psi (2.5 bar)
19 inch wheels front 32 psi (2.2 bar)
rear 36 psi (2.5 bar)"

Also because of the different measuring systems the TPMS and a tire guage will always show different amounts. There is a thread here explaining the difference (TPMS Accuracy I think).

Did you have a tire dealer or Porsche do this? How much did they charge?

19" summer tires are (by the book) supposed to run 32# front and 37# rear cold measurement. I usually run mine at around 34-35# front and 39-40# rear that feel much better to me at those pressures. YMMV...

brad

i went to a place that specializes in wheels. it was an easy job. $60

And as Santa Fe mentioned the manual shows 36# for the rear.

I think it has been mention before that there is the 1# rear discrepancy between sources. 37# for the rear is what it says on the door frame of my car.

Oh well - the pressure changes a fair amount more than that while driving anyway.

Did that include the mounting and balancing?

I'm with you. I've been running my 19" at 34F 38R for less understeer, although still excessive. I run my 18" at 32F 36R for the same reason. (29/36 by the book).

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Dan

The tire shops around here post a charge of $10/wheel for TPMS service. That is on top of mounting and balancing.

they didn't unmount the entire tire. they just unmounted 1/2 of the tire and put the sensors on. it looked pretty wasy. then they checked to see if it was balanced. they were all pretty much balanced

r6tanz, all the other TPMS posts are in the Tires & Wheels forum. Do you mind if I move this in a couple of days to that fourm