Update:
The OZ alloys appear to be a radius seat so I'am using the 25mm original bolts.
On both the standard 8v and OZ alloys there's 17mm of thread to screw into the hub/disk.
I checked all threads were OK, replaced the fractured bolt (and another that appeared to have stretched!!) and once fitted carefully torqued all bolts in sequence to 110 NM with no probs. I think I may have been a bit aggressive in tightening them before!
The following was lifted off the Seat electronic w/
shop manual:
Lightly grease the threads [this is unusual lot of cars rely on dry threads]
-1- and the ring -2- with lubricant paste according to the → Parts catalogue ;
ensure that grease does not get to the brake system elements.
t Lightly grease the thread -1- and the stud -2-
Wheel assembly
t Tightening torque: 50 Nm
– Lower the vehicle to the ground and tighten the wheel nuts in diagonal pairs.
t Tightening torque: 120 Nm
– Check that the brake disc tool?? and the wheel hub thread match up.
The thread of the wheel nuts should not come into contact with the brake disc tool.
Bolt the wheels as follows:
– Hand tighten the wheel nuts evenly.
– While the vehicle is still raised, tighten the wheel nuts in diagonal pairs.
some bits appear lost in translation??!!