Grab and release when braking 1994 Volvo 850

sonydst · Post by **sonydst** » 10 Jul 2010, 13:01

When braking, the stop is not smooth. There is a noticeable grab and release feeling when braking. Slight vibration in steering wheel but the main symptom is the lack of smoothness when braking.

I have read a lot on this forum about the tendency for the rotors to warp. Is that what is going on with my Volvo 850? If the rotors should be replaced, would you recommend just the front or the rear or both? What replacement brand would you recommend and do slotted/vented rotors make a difference in preventing warping in the future?

Any suggestions are appreciated. Thanks

Post by **polskamafia mjl** » 10 Jul 2010, 13:57

The vibration sounds to me like your rotors are in fact warped. I would suggest replacing all 4 corners. I am running Zimmerman cross-drilled rotors and Akebono Euro Pads. Some people swear by cross-drilled or slotted rotors while others prefer the OEM style ones. The most important thing to prevent warping is to prevent the rotors from overheating. When sitting at a stop light roll forward every 5 seconds or put the car in neutral and set the e-brake. When you keep your foot on the brake for an extended period of time, then only one part of the rotor absorbs the heat from the pads. When this happens, that one spot warps creating vibrations and weak brakes. If you can spread that heat around the rotor then the risk of warping is significantly lowered.

Post by **Pauloil** » 10 Jul 2010, 19:39

somewhere is a post about conditioning rotors, over on volvospeed
here's some other ideas:

http://volvospeed.com/vs_forum/index.ph ... ntry389280