blue meanie wrote:

..... mean your speedo will be well out considering the extra half inch ( ) ?

My current Stormers/Grabbers run spot on re figures on speedo versus GPS reading.
The LTZ's give an extra 10mm sidewall height [=142.5] over my 295/45/20Grabbers [132.75].
So yes, the speedo will be out, but only slightly.
BUT many run a 255/45/20 tyre [sidewall =114.75], thats 18mm diff to my Grabbers, so their speedo will be further out.
Hence when showing 70mph, actual speed for them will be around 66/67mph
Where as mine at 70mph will poss be an actual speed of 71/72mph
I can live with that to gain a taller sidewall.

hope that makes sense