Vibration/Groan when braking slowly

[nwkurzrep]

Hello, I own an 95' 850 turbo and have had the most frustrating experience recently. A little history first. In February of this year I had my front pads replaced and rotors turned. I began hearing a noise soon after and returned the car to the mechanic only to be told that they couldn't find anything. Soon afterwards, I began to get a vibration/groan that became present when stopping. This would really only be noticed at speeds of under 30 miles/hr., but most evident when rolling gently to a complete stop. Months later, my ABS light began coming on and the sound became worse. The initial mechanic still found nothing wrong with the brakes but noticed the front passenger side need a new drive shaft. We replaced the shaft and the car still made noise. The mechanic then told me he couldn't check the ABS so I went to a Volvo technician. The Volvo mechanic noticed a bad ABS module/relay and front right tie-rod, along with the front right pad not gripping the rotor correctly. This caused the rear rotors to become warped from overcompensating. This had to be causing the vibration and groaning sound when stopping right? Now we're already at $1850. All four rotors were replaced along with new pads and calipers checked. Still vibrates/groans to a stop. The mechanic, who works on BMW's, Benz' and Volvo's has never heard anything like it and is out of ideas. He's pissed too, but is sure the brakes have been eliminated as a problem. The problem never occured when the car was on the rack bearing no load. I tested it this evening and found that it happened when going forward, but not in reverse. What's up with this? Is this a transmission deal or what could it be? Mind you, it only occurs or is noticed at very slow speeds and when applying the brakes.

Please help from anyone, I've owned this car for 2 yrs now and it had a perfect maintainence record and I've now averaged almost $100 per month in repair/upkeep.

regards,

Andy

[Guest]

my past experience with braking noise is as follows:-

Original Nissan Brake pads = no noise

Original Volvo Brake pads = no noise

Anything not original = some braking noise ....its just more or less proportional to the price you pay for your brake pads.

Just bear with the noise....its normal...unless you want to change to

1) original pads with
2) original shims and with
3) original brake pad grease

if either one of above is missing then you have noise.

hope this helps

[florida]

ours did the same, the dealer made the problem go away till his 30 day warrenty was up now its back, the whole car shutters sometimes.. scary, ours is a 94 850

[Guest]

If the "fix" lasted only 30 days, the prime suspect is that only normal grease was used....special brake pad grease has to be used. This should fix this.

[jimbo.k]

hi, dont really know if its the same prob, but when i put mine in sports mode then i get this vibration under heavy breaking from bout 30mph down, just had the wheels balanced and the brakes checked by volvo and they cant find the prob, when i turn the engine off it resumes back to normal, v strange-if you get the answer let me know coz i havent had this car long.
jimbo.k

[OJF]

I

[jimbo.k]

hi ojf,
thanks for the info, but this seems really strange. the groaning doesnt happen when i am not in sports mode? i have tried stopping really hard in economy mode no probs at all, even tried braking lite but cant reproduce the effect. however i have tried it in sports mode and it not happening now. very strange indeed. on another matter when i get the car above 90mph i get a vibration in the car, this dissappears above 105mph! i just got the front wheels balanced at volvo dealer and have still have the same prob? do i need to get the rear wheels balanced as the guy at volvo said it didnt matter much?
the car doesnt pull to one side even at high speed, there are no obvious clunks or rattles.
apart from that the car is great averaging 25mpg around town.
if you could help solve this problem i would be most grateful
regards
jimbo.k