98 V70XC brake vibration/rubbing noise

[hogie50]

Looking for suggestions fo cause of brake vibration. Seems to come through steering wheel and pedal so replaced front rotors (Zimmerman Z-coated) and pads (Volvo). Even replace one of the caliper carriers as it looked very worn. All that work and still vibration. Local garage suggest unlucky and had bad New rotors. Never had that problem in 35 years so any other suggestions? also they said maybe I should replace rear rotors, but wouldn't you feel vibe in your butt through the seat?

Also from the rear I get a rubbing/chaffing noise. I had to replace the park brake cables as one was seized and other broken. Replaced park brake shoes also. I took rotors off again to look for rubbing noise and noticed one rotor still had 50% width still rusty. Could it be all my brake issues are a bad rear rotor? I have new rear rotors (just need to get pads). Should I try to replace them or any other suggestions?

Many thanks from Calgary, Canada

[JRL]

Are you SURE you felt it through the steering wheel?
Feeling it in the pedal is more rears than fronts.
If you also felt it under your rear end (seat) that's rears

[hogie50]

Thanks for the quick reply. To be sure I will go back out and try it again. It is less noticeable at low speeds, but much worse at higher speeds. Like I said, I did NOT notice it through the seat, but through the pedal and steering wheel. Before I take any more of your time I will take the car for another run and re-check and update you on symptoms!

[hogie50]

Hi JRL, I took the car for another run and worked the brakes hard. Not too much vibration at less than 50km/h. It is hard to be sure where the vibration is coming from. From what you said if it is from the rear, then will feel it through the peddle which is where I feel it. Steering wheel vibration I think may be just me transferring the vibration to the wheel from my foot. So I think the next step is to replace the rear rotors over the weekend. Let you know how it goes.

I have another question from my test run. Front brakes smelled VERY hot on return from run, and I noticed the from RH (driver side) wheel was too hot to touch. LH (Passenger side) was hot but not nearly so as I could keep my hand on the wheel. When I replaced the front rotors, I also replaced the caliper bracket with a new Volvo part on the RH side. This came with a thick (1mm) plastic type coating on it. I asked Volvo if I should remove it before installing the brakes but they said no, even though the pads were hard to fit as this stuff filled the slider areas too. Originals don't have this. Should I take the bracket back off and remove this stuff?

thanks again.

[JRL]

Smell sounds like a bad caliper (or related)
When you brake, does it brake 100% straight or is there any pulling?

[hogie50]

Pulls straight. I am going to take the thick coating on the new caliper bracket off and replace it on the non-contact surfaces with regular caliper paint I have. I'm hoping it is just the pads that can't release properly due to the coating. I've also got new rear Volvo pads so will aim to change these ASAP and the front bracket over the next couple of evenings. Thanks for the continued support. Also spoke to Volvo when picking up the pads and they think it is also the rear rotors and suggested removing the coating (apparently they don't normally).

[hogie50]

Turns out BOTH front AND Rear rotors were warped. Never had a set of rears go in 35 years of owning Volvos. Seize yes but not warp!

Sorry JRL for the delay getting back on this, but the water pump decided to let go. My mistake (cheap Scot) for not changing it when I just did the cam belt and serpentine.

Rubbing noise is still there, but now believe it is a RH rear wheel bearing or diff bearing. Certainally gets louder when turning left, and lessens on turning right. Not the usual groan/droan of a wheel bearing. More ofa rubbing sound which increases with speed and park brake/brake applicatoin makes no difference.

This car almost brakes with the regularity of my wifes' Audi A4! At least I can repair most of the stuff on the Volvo (won't go near the Audi as I'd probably set it on fire!!).

Thanks for the help.