Hi everyone. I'm hoping someone can help me figure this out. My wife and I recently purchased a '97 850 wagon with about 50K on it. It's been a great car so far. Occasionally, during braking, we'll hear a humming noise coming from the front right of the car. The noise doesn't happen everytime we stop. When it does occur, it happens right at the very end of the stop, I'd say about 2 seconds before we're completely stopped. Perhaps by total coincidence, the noise started about a week ago when the weather started getting a little colder here (20 degrees or so at night and 35 or so during the day). During a typical day, the noise might occur during the first five or so times that I use the brakes, but won't occur again for the rest of the day.

I took it to the service garage where we bought the car and the mechanic could not recreate the noise. He suggested that it's probably the ABS pump building up pressure(?) He said he's sure it's nothing to worry about. While his explanation doesn't satisfy me, I have no clue what it might be.

Interestingly, I found a post from a few years ago describing the same phenomenon in a '96 850. Unfortunately, no one responded to that post. (Here's the link: http://brickboard.com/ARCHIVES/1997DEC/6261.shtml).

Any thoughts?

Thanks!

Aaron

Are you sure its the brakes? Is your heat on when you hear the noise? It somewhat sounds like the blower motor goin bad. Mine does the same thing (I'll be replacing it soon). Mine sounds like a slow moaning.

Ben,

Thanks a lot for taking the time to help me out. That sounds like an excellent suggestion - especially given what happened yesterday. A friend gave me a ride from the airport in his '96 854 and his car also makes the humming (or moaning) noise from the front right, but in different situations than my car does. My jaw dropped when I heard it, because it is definitely the same noise. As you suggest, my friend says it only occurs when the blower is on, but not all of the time, and only when the blower is on low not high. Strangely, the noise goes away when he hits the breaks -- exactly the opposite of my situation.

My plan is to try to recreate the noise this morning with and without the blower on. I'll let you know what happens.

I guess I have two questions for you in case it is my blower motor:

1) About how much do you figure a blower motor costs?

2) Are they tough to replace?

Thanks a lot!

Aaron

Aaron:

Had my blower motor replaced yesterday. Done under VIP warranty so it was covered. Invoice notes that cost would have been $255 total. Breakdown appears to be about $200 for fan motor - rest for labor.

Sorry, but don't know anything about do-it-yourself replacement....

Thanks to all of you for helping me with this bizarre little humming/moaning noise phenomenon. Ben was right, even though the noise occurs during the last few seconds of braking, it isn't the brakes -- it's definitely the blower motor! If I turn the blower off while the noise is occurring, the noise stops. Pretty compelling evidence. Also, if the blower is in any other position than the first position (i.e., lowest setting), the noise doesn't occur at all, which explains why the noise was so intermittent!

Thanks a lot - you all saved me a trip to the shop!

Aaron,

Thats right, the sound only comes on if the fan is on a low speed. Mine seems to happen in both situations- when braking, AND when not braking. I'm not sure about either the cost nor difficulty of replacing it. I believe I read on this board awhile back and remember someone saying that the Volvo blower from the dealer costs somewhere around $150. Again, I'm not positive on that one. Good luck...

It sounds like you are getting brake chatter or vibration. You may want to check to see if the pads were replaced. Chances are they have been replaced recently as the car was just sold and most dealers do this automaticly to insure that the vehicle passses safety inspections. Odds are that when the pads were replaced they did not get anti-vibration coating and new shims. I am also pretty sure that they did not get the grease on the pins and other needed areas. Check out www.volvospeed.com/bay13 for some info. I think that the site has some detailed info on the right way to do a brake job on these cars. Also, while you are down there looking at the brakes, check the thickness of the rotors and also look for grooves and glazing. If you bought the car from a Volvo dealer, then chances are they did it right. If you got it from an "other" dealer, check the brakes.

Prospero

Thanks a lot for the advice. You're right, I did buy the car from a non-Volvo dealer.