As the topic says, this isa brake question. As you may have heard, we here in Washington State have had to deal with a REALLY bad windstorm and flooding (in fact I just got my power back after 4 days)

Anyway, my son was out in the 850 the other day getting some emergency supplies, and he had to drive through about 100 yards of12 to 15 inch deep water. He drove slowly through the water, but ever since then if you apply the brakes normally from speeds above 25 MPH, you can feel a light pulsating through the steering wheel and the brake pedal. Slower than 25 MPH, and you do not feel it. Also, if you apply the brakes firmly, you will not feel the pulse. Same if you barley apply them. You only feel the pulsing from speeds above 25MPH with normal brake application.

My guess is a brake rotor was warm, and when he drove through the water it rapidly cooled it and warped the rotor.

Looking for ideas for the forum.

Thanks,

Glenn

 

Hate to agree with you but I think that is exactly what happened. Your ABS light is not on is it? The reason I asked was when the ABS module started to go bad in my sons 850 there was a pulsing feeling, not all the time, intermittently. I still think you have a warped rotor. Volvo does not recommend turning the rotors.

 

I agree on the rotors as well.

 

Well, since it looks like I will be in the market for two new front rotors, I went and checked Groton's site and autohausaz. They offer Brembo, Zimmerman, and PBR. The PBR are the least expensive, and I believe Zimmerman was the costliest. Any recommendations on brand?

Glenn

PS, No ABS light at any time.

 

It's really just a hunk of metal.

I got Brembos just because it's Brembo lol.

 

The brembo's are OEM.
I have brembo's on the white one.
But was also thinking about buying a set of drilled and slotted from E-bay. There is some for $99.00 and up for all 4.
Im still trying to decide what I am going to do.
But after having to just spend almost $300.00 for a new Radiator that has to wait some.

 

Tech, let us know if you go the ebay route. I've been watching some D & S rotors but was unsure of quality.

 

I have been watching about 4 different sets on there.
Once I got the spare cash I plan on buying a set bot sure which ones though.

 

Last question, if I buy new rotors, can I use the old pads (They are only about a year old with 10K on them)? I have heard an old saying that you can use new pads on old rotors, but not old pads on new rotors

Glenn

 

Hi Glenn,

If it were my car, I would replace the pads as well with OEM (Textar fronts & Volvo rear, etc). Butwait tillwhat others have to say before making a decision.

As to rotors, I believe there were a few different OEMs, such as Brembo, ATE, and I wonder if Zimmermann was one of the OEMs as well.

When you replace the rotors, service publications say you need to replace the caliper bracket bolts for fronts and the caliper bolts on the rears. I replaced mine when I did the rotors (Brembo x4) and used a torque wrench to be sure. See what Tech would have to say on this.

I would also clean all components, sand off rusts if necessary, apply slider pin grease for the fronts, and then dab either silicone grease or molybdenum grease (CV-joint grease) on all metal-to-metal contact surfaces, except the friction surfaces to prevent high-pitch squeal. 90% of the members have cured the rear squeal with half-shims, but mine kept squealing even with the half-shims,until I applied CV-joint grease. After that, the squeal never returned.

Well, I'll let others provide you with different opinions.


JPN

 

If I have to reuse the old pads I scuff them up with some sandpaper and then reinstall them.
Never had any problems from doing that.

As far as teh Hardware if new comes withe the rotors I use them if not I reuse the old and never have a problem.

 

So there could have been a conspiracy between Volvo & Haynes as to replacing the nuts & bolts with new ones whenever they're disturbed...

Gaaaa[8D]!!


JPN

 

Well, I found aset of Brembo disks on sale for $23 a disk, so I will be buying them today. I will also try scuffing the pads as Tech mentioned. However, I just found out today from my son that the heater motor is starting to squeak and squall again. I lubed it this summer and it seemed to be good, but now....looks like I will be replacing the blower motor *sigh* looks to be one of those months!

Glenn

 

Yes Glenn that is a part of owning an 850 that we all have to go through.

Behr makes the replacement, or Bosch sells one without the cage. I bought the Behr as the original cage was way too filthy to clean and seemed to be missing some tiny balance weights.


JPN