tkta02

When braking from higher speeds.... 65+MPH MY ABS system activates and the tires definately arent slipping on dry pavement. It didnt happen before I installed my 18X9 Front & 18X10 Rear Boyd Coddington Smoothie II's. The fronts are 275/35-18 and the Rears are 305/35/18. I took the car to the GM dealership and they were unable to do any computer programming for the tire size.

What could be happening? Any Advise?

Thanks,
Todd

02 NBM WS6 'Vert

TNTramair

iTrader: (15)

im not sure about sizes on tires...but...if your overall outside diameter of your tire is more/less than factory (ex: 25" outside diameter stock tire..and you put on a 26" or 24") your abs will come on cause the wheels are now turning more/less speed than the factory setting sees..therefore thinkin the wheels have to be slippin b/c this is happening. this is just a possability. also if one of your speed sensors are bad it may do the same thing and its just a coincedence that it started happening after you installed the rims...good luck..hope this helps.

jimmyblue

iTrader: (11)

It's the difference in diameters, making the wheels
rotate at different speeds for the same vehicle speed,
being interpreted as slip.

This is something I recently asked about. I guess we
have one example now of "how much is too much".

If anything were to get programmed I reckon it would
be the ABS "brain" but nobody messes with that it seems.

I would say to go put some 275/40 or 285/35, 285/40 on
there and try again. Maybe see if you can find a set to
borrow and try on, rather than taking an expensive gamble.
Go up to a sidewall height in front that is about the same as
it is in back.

If it's not too much trouble, could you measure the actual
tire circumferences and post them up in the name of
science?