1997 Volvo 855 GLT Brake "Catastrophe" repair 1330273

Post by **dosbricks** » 16 Nov 2014, 18:26

Does this pin actually have any value other than keeping the rotor snug to hub? Is there a purpose to orientating the wheel the same for the life of the car? This mystery of Swedish engineering needs to be probed in greater depth.

Post by **erikv11** » 16 Nov 2014, 22:24

The purpose of the pin is to keep the lug holes in the rotor aligned with the threaded ones in the hub. Otherwise the rotor can spin when you are putting on the wheel.

Lots of cars use this kind of pin, sometimes there is a hole in the wheel and sometimes not, sometimes it fits into cavities in the wheel (i.e. sometimes the wheel can go back on in any orientation).

Post by **Ben850** » 17 Nov 2014, 11:35

erikv11 wrote:The purpose of the pin is to keep the lug holes in the rotor aligned with the threaded ones in the hub. Otherwise the rotor can spin when you are putting on the wheel.

Lots of cars use this kind of pin, sometimes there is a hole in the wheel and sometimes not, sometimes it fits into cavities in the wheel (i.e. sometimes the wheel can go back on in any orientation).

While doing the rotors and pads on my friends Honda, I came across tapered Phillips screws as opposed to pins.
They were not about to be removed with a Phillips and I had to simply drill them to get the rotors off.

They were not missed when I installed the new rotors.

Post by **erikv11** » 17 Nov 2014, 11:39

Agreed, they certainly aren't important. I just meant to clarify their actual intended purpose.

Post by **abscate** » 24 Mar 2020, 05:55

Bumped for the awesome successful extraction of a broken bolt and documentation by jreed. Also the perils of using a torque wrench on the low end of its range are exposed

The official MVS torque for these bolts is six finger pounds

+1000 mvs points for hyperbolic use of catastrophe

Added part number for the rotor guide pin to title