2000 saab 9-3 brakes are dragging after vehicle warms up; replaced the master cylinder as the old one was difficult to push in / actuate during bench bleeding and wouldn't retract easily; however brakes still lock-up, seize, drag while driving. Seems to affect all four wheels. Trying to troubleshoot without spending money on replacing every single part of the brake system. Did replace the booster/servo not too long ago due to having to stand on the brakes just to get the car to stop. Suggestions include: 1. Did I screw up something with the servo replacement? 2. Caliper issue? 3. Emergency brake need adjustment? 4. Proportioning valve issue? 5. Brake lining/hoses swelling? 6. ABS module or sensor issue? Looking for help so I can send this car with my son to college this Fall.

Thanks; I've suspected that free play could be an issue but I'm hesitating to pull all of this back off (m/c, booster, pedal linkage, etc.). I don't remember there being an adjustment assembly on the booster/servo. I checked to see when I purchased the servo and it was exactly one year ago (8/18/2008). I performed a check of the servo as follows: 1) run vehicle to warm-up, 2) apply the pedal and hold, 3) stop the engine while pedal still depressed, 4) pedal should not rise nor sink while holing the pedal for 30 seconds. Problem is ... my pedal rises after about 10 seconds. Could I have a bad brake booster/servo; even though I replaced it less than one year ago? I thought I was buying a new unit. I also performed the following check while the engine was off and rotors were cool: 1) compressed the cylinder with a clamp to release the pads from the rotor, 2) pressed the pedal until pad engaged with rotor, 3) seemed to operate fine (i.e., no issue with cylinder/caliper free travel), 4) release brake and was abel to turn rotor freely with minimal binding. Then when I started the vehicle the servo unit kicked in and without even applying brake pedal the rotor was very difficult to spin. Brake booster problem or still suspect free play? Thanks in advance for opinions/advice. Thanks; I've suspected that free play could be an issue but I'm hesitating to pull all of this back off (m/c, booster, pedal linkage, etc.). I don't remember there being an adjustment assembly on the booster/servo. I checked to see when I purchased the servo and it was exactly one year ago (8/18/2008). I performed a check of the servo as follows: 1) run vehicle to warm-up, 2) apply the pedal and hold, 3) stop the engine while pedal still depressed, 4) pedal should not rise nor sink while holing the pedal for 30 seconds. Problem is ... my pedal rises after about 10 seconds. Could I have a bad brake booster/servo; even though I replaced it less than one year ago? I thought I was buying a new unit. I also performed the following check while the engine was off and rotors were cool: 1) compressed the cylinder with a clamp to release the pads from the rotor, 2) pressed the pedal until pad engaged with rotor, 3) seemed to operate fine (i.e., no issue with cylinder/caliper free travel), 4) release brake and was abel to turn rotor freely with minimal binding. Then when I started the vehicle the servo unit kicked in and without even applying brake pedal the rotor was very difficult to spin. Brake booster problem or still suspect free play? Thanks in advance for opinions/advice.

We just shimmed the m/c off the booster about 1/8 inch using washers. Test drove and much better response; very little if any drag after a few trips around the subdivision. Came back home and removed the shims, reconnecting the m/c on the booster and took another test drive ... brakes are dragging/locking up again. In the meantime I found the old servo/booster unit in my garage (I keep too much crap like that). There appears to be no adjustment option on the length of push rod. This is driving me nuts (no pun intended). Any other thoughts? We just shimmed the m/c off the booster about 1/8 inch using washers. Test drove and much better response; very little if any drag after a few trips around the subdivision. Came back home and removed the shims, reconnecting the m/c on the booster and took another test drive ... brakes are dragging/locking up again. In the meantime I found the old servo/booster unit in my garage (I keep too much crap like that). There appears to be no adjustment option on the length of push rod. This is driving me nuts (no pun intended). Any other thoughts?

One other bit of useful information. I noticed fluid on the top of the brake ABS hydraulic unit the other day. I thought it was perhaps brake fluid spilt the other day when we replaced the master cylinder; since the ABS unit is next to the m/c. I wiped the ABS unit clean. Today, after driving the vehicle as described above, after the m/c shim test, I noticed a fresh accumulation of fluid on top of the brake ABS hydraulic unit again. I doubt this is normal. There appears to be two small ports on top of the unit, perhaps pressure release ports, and I suspect this is where the fluid is leaking. I'm hoping the ABS unit is not the problem as these run $900, plus. Does this offer any meaningful data in troubleshooting the problem with brakes dragging? One other bit of useful information. I noticed fluid on the top of the brake ABS hydraulic unit the other day. I thought it was perhaps brake fluid spilt the other day when we replaced the master cylinder; since the ABS unit is next to the m/c. I wiped the ABS unit clean. Today, after driving the vehicle as described above, after the m/c shim test, I noticed a fresh accumulation of fluid on top of the brake ABS hydraulic unit again. I doubt this is normal. There appears to be two small ports on top of the unit, perhaps pressure release ports, and I suspect this is where the fluid is leaking. I'm hoping the ABS unit is not the problem as these run $900, plus. Does this offer any meaningful data in troubleshooting the problem with brakes dragging?