Hope everyone is enjoying their G35 as much as I am.

I have a question, I just replaced my front rotors and pads because of a TERRIBLE vibration when braking that basically felt like the car was going to fall apart. My question is when I was changing out the pads, I was pressing on the guide pins and noticed the one guide pin on each side (the one with the rubber insert) was hard as a rock to move. I tried moving it back and forth and got a little play. The other guide pin (without the rubber insert) moved just fine no problem at all on both sides. So Is that how it is supposed to be?

I can't remember last time if they were like that or not because I know I took them out and put grease in them. They were a pain in the butt to get back in. the rubber insert kept sliding over the pin and catching the caliper hole.

Can someone please explain what this rubber insert is and what it's function is? I know you can loosen that bolt and then take the other guide pin bolt out and just swivel the caliper up (or down), so is that what it's for?

I'm driving a 2008 g35x

 

Sounds like your guide pins are seizing up. They should both move freely in and out. Sometimes, if water makes their way in, they will start to gunk up and be difficult to move. When they don't slide in and out freely, the caliper binds and you get uneven wear of the pads. The inner one tends to wear more.

I forget the purpose of the rubber ring on one of the pins. It was explained a long time ago and I've just since forgotten. However, do NOT use petroleum based caliper grease on tese if you try to clean and relube them. The petroleum will swell the rubber and it will stick even more. Use silicone based grease. Hopefully you didn't use petroleum grease the first time as that would be why the pins are stuck now.

You really need to try and remove both pins, clean them up well, and regrease them so that they easily slide in and out. If they are seized up, you'll need to replace the brackets. I see that rockauto.com has the rears for $25 each, but not the fronts. If you can't locate front brackets, you'll need to buy reman calipers and swap them on.

BTW. During one brake job, I had a tough time with the rubber sleeve getting the pin back in the bore. I ended up taking the rubber off for good. It's been a number of miles without issue.