mctoothdr

wheel/tire size increase and resultant TPMS/ABS Code

went from 18" factory wheels/tires to a much more aggressive 20" setup. Instantly had TPMS sensor and ABS lights appear on dash.
I have NOT reset the TPMS system (appears relatively easy to do from column computer stalk)...will do shortly. Not so sure of any "remedy" to the ABS code. Has anyone had similar issues when
increasing wheel/tire size?

mctoothdr

Sorry...my vehicle is a 2008 997.2 C4 Cab

Petza914

The tire size is more important than.the wheel size. What did you install on those 20" wheels?

mctoothdr

Fronts are 245/30-20
Rears are 325/25-20

Petza914

I ran some comparison numbers for you from the stock 19' wheel setup since I know those numbers off the top of my head and your tire sizes should not be causing the issue as the rolling circumferences on the 20" wheels are within 3% of 19s and the F to R percentages on the 20s are also within 3% just like with the 19" setup.

Compared sizes are below


Stock 19" sizes - rear smaller than front




19" fronts compared to 20" fronts (not too important, but pretty close anyway)




New 20" setup with rears smaller than fronts and almost exactly the same amount smaller percentage wise




19" rears vs 20" rears - almost the same

So, not sure why you're having this error unless you damaged or knocked loose a wheel speed sensor when changing the wheels.

mctoothdr

will start with TPMS evaluation...signal being sent, etc.. Go from there. appreciate the inciteful response

groovzilla

How did it go resetting the TPMS?

Took my car for drive today and noticed TPMS warning. When I use the short stalk to access the TMPS data, it shows tire pressure on the front 2 tires not the rears.
I checked and all 4 tires have proper pressure.
This happened a few months ago and warning went away and all 4 tire pressure readings were visible on dash.
I'll figure out how to do a reset and see if it calibrates.

mctoothdr

Should know tomorrow. Had a local tire shop check sensors that were already mounted on the wheels I purchased. All 4 were not sending signal! We’re assuming sensors were no good..the gentleman I purchased from said he used sensors he had when mounted a while back..but disconnected his TpMS because he didn’t care about errors..
Well….I ordered new HUF sensors (433mHz) from Tire Rack..supposedly preloaded for the 997. They say they just need installed and then relearned from cars computer.
That happens tomorrow morning! Otherwise…wheels/tires handle well/I like the appearance…just hope car acquires the signal from these new sensors

mctoothdr

HUF sensors installed this morning. AFter about 11 miles of " learning"..all good! No more TPMS error lights, just accurate pressure readings!

groovzilla

Good news. I'm headed to our beach house today overnight with my wife(90 mile drive) and will set the TPMS learn mode and let you know how I make out.
Since all sensors 4 were working about 2 months ago before my car sat in garage and now only front 2 are working, I am pretty certain it is not a dead batteries since 2 went out at same time.
\

mctoothdr

Great…..beach sounds even better!

groovzilla

Wound up taking SUV
Will have to rest Sensors some other time...