pulsed vibration or shudder when braking

[nailers]

We've been gettingi vibration or shudder when braking. At slow speeds it definitely feels pulsed like it's rotational. The car is an 01 with 170000 miles. From what I've read here and elsewhere, it seems that warped rotors are unlikely and that uneven buildup is more likely the cause. Maybe from the brakes not be set properly or some evironmental conditions when it's not used.

I’m looking for a more experienced opinion how to proceed. It would seem the most cost effective way would be to replace the rotors and pads while checking the calipers for proper function. Does that sound correct? And is that a difficult job on this car? I’ve replaced the rotors and calipers on an older Toyota Land Cruiser so I’m not totally a noob. I’ve also found something about a TSB 10005319 issued in 2003 for brake vibrations, analysis and corrective action, but I can’t find anything else about it. It seems unlikely to me that an issue from that long ago is just arising.

I appreciate the help.

[howardc64]

Brake job is easy on this car. Only tricky spot where even non brake job noobs (like me) mess up the first time is the put the caliper tensioning springs back wrong. Take a pic before pulling that off so you know exact how it goes back. Resource section on this website has the Volvo factory directions on the brake job.

As for why you have shuddering when braking. Best to open it up and take a look. Check pads for even wear, no leaks from caliper etc... I had a rear brake pad jam on this car and wore unevenly once because the alloy bracket the pad rides on was manufactured out of spec and jammed the pad ears. But this seemed to be a rare occurrence and I've not read anyone else encountering this. Anyhow, the brake system is pretty simple on this car, pull the wheel off and inspect it to see if you can tell what is going on.

I don't know if loose suspension+steering bushings+ball joints can cause what you are experiencing. Just a thought at 170k miles and perhaps with some worn front end parts there.

[MacNoob]

Are the brakes otherwise in good shape? No bad gouges in the rotors, lots of pad left, calipers working properly, etc? Florida has to be a hotbed for rust if the car isn't used regularly.

I'd think about going out and doing a few progressively harder 60 mph - 10 mph almost-stops until the brakes are nice and hot, then drive easy for awhile and let it all cool down. That should clean any gunk off the rotors if that's what your problem is. Google some stuff on brake bedding.

[Xheart]

We've been gettingi vibration or shudder when braking. At slow speeds it definitely feels pulsed like it's rotational. The car is an 01 with 170000 miles. From what I've read here and elsewhere, it seems that warped rotors are unlikely and that uneven buildup is more likely the cause. Maybe from the brakes not be set properly or some evironmental conditions when it's not used.

I’m looking for a more experienced opinion how to proceed. It would seem the most cost effective way would be to replace the rotors and pads while checking the calipers for proper function. Does that sound correct? And is that a difficult job on this car? I’ve replaced the rotors and calipers on an older Toyota Land Cruiser so I’m not totally a noob. I’ve also found something about a TSB 10005319 issued in 2003 for brake vibrations, analysis and corrective action, but I can’t find anything else about it. It seems unlikely to me that an issue from that long ago is just arising.

I appreciate the help.

Where is vibration, pulse most noticeable. We, would suggest driver and passenger(s) feel the vibration.

[Steve F]

howardc64 already mentioned front end components, I was going to suggest that as well. I had severe vibration under braking and thought the rotors had warped, even though they were fairly new. I replaced leaking struts, control arms with shot bushings and loose ball joints and then had an alignment done. The car drives like new and the brake vibration is gone.