Bill4209 Posted August 19, 2008 Report Share Posted August 19, 2008 On my 98 Deville and the front rotors and pads are brand new.It was pulsating before I changed the rotors and pads also.Its not an ABS related hard thumping either because I know what that feels like.I can feel the pulsation on the outside of the car, in my seat, in my steering wheel,and in the pedal.It is for sure coming from a wheel but I cant tell which one or why.Any suggestions would be helpful before I waste money on a mechanic.Maybe rear rotors which are still original????? Link to comment Share on other sites More sharing options...
KHE Posted August 19, 2008 Report Share Posted August 19, 2008 On an isolated area, use the emergency brake only to stop the car. That will leave the front brakes out of the equation. If the car vibrates, the rear rotors are the problem. Kevin '93 Fleetwood Brougham '05 Deville '04 Deville 2013 Silverado Z71 Link to comment Share on other sites More sharing options...
Cadillac Jim Posted August 19, 2008 Report Share Posted August 19, 2008 You might also look at your front rotors while rotating the front wheel slowly with your hand and look for a big rough patch where the pads rested when you parked with the brakes hot. If so, a little patience with some 400 grit sandpaper would fix it, or you can get the rotors smoothed at a machine shop. -- Click Here for CaddyInfo page on "How To" Read Your OBD Codes-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data -- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC Yes, I was Jims_97_ETC before I changed cars. Link to comment Share on other sites More sharing options...
jking220 Posted August 19, 2008 Report Share Posted August 19, 2008 Make sure all of your front end parts are ok, like tie rod ends and ball joints. I have a tie rod end thats pretty loose right now and it causes a bad shake in the front end, which usually gets much worse under braking. Jonah Link to comment Share on other sites More sharing options...
Bill4209 Posted August 19, 2008 Author Report Share Posted August 19, 2008 You might also look at your front rotors while rotating the front wheel slowly with your hand and look for a big rough patch where the pads rested when you parked with the brakes hot. If so, a little patience with some 400 grit sandpaper would fix it, or you can get the rotors smoothed at a machine shop. Front rotors and pads are 2 days old.It pusated before I changed them also.I thought that they were the cause of my problem....... Link to comment Share on other sites More sharing options...
Bill4209 Posted August 19, 2008 Author Report Share Posted August 19, 2008 With the right rear off the ground the wheel does not spin freely.It gets tight in one spot and I must use force but not much force to get it past the tight area.It spins free again then stops in that same area again.I am thinking rotors have high and low spots and need new rear rotors.What say you fellas?????Could this be my pulsating pedal? Link to comment Share on other sites More sharing options...
JimD Posted August 19, 2008 Report Share Posted August 19, 2008 With the right rear off the ground the wheel does not spin freely.It gets tight in one spot and I must use force but not much force to get it past the tight area.It spins free again then stops in that same area again.I am thinking rotors have high and low spots and need new rear rotors.What say you fellas?????Could this be my pulsating pedal? Almost guaranteed to be (at least part) of the problem. And it could be as simple as an uneven coating of brake pad material on the rotor. If that is the case, you might correct the problem by putting some serious heat into the rear brakes by using only the Park brake pedal to slow the car from 45 MPH to about 10 MPH several consecutive times (about 10 times should be good). Do not be concerned if you see smoke and can smell hot brake pads; that is what you want. Speed at 45 MPH and use Park brake down to 10 MPH, accelerate to 45 MPH and brake to 10 MPH. Repeat ten times. Park the car for an hour to allow the parts to cool; do not apply Park brake. Repeat if necessary. I have no experience with your year/model, so you are on your own to deal with the Park brake pedal latching arrangement. Jim Drive your car. Use your cell phone. CHOOSE ONE ! Link to comment Share on other sites More sharing options...
KHE Posted August 20, 2008 Report Share Posted August 20, 2008 As long as the vacuum solenoid on the emergency brake is working properly, it shouldn't latch while the trans selector is in Drive. After heating up the pads, drive for a few miles to help cool them. Kevin '93 Fleetwood Brougham '05 Deville '04 Deville 2013 Silverado Z71 Link to comment Share on other sites More sharing options...
Bill4209 Posted August 20, 2008 Author Report Share Posted August 20, 2008 As long as the vacuum solenoid on the emergency brake is working properly, it shouldn't latch while the trans selector is in Drive. After heating up the pads, drive for a few miles to help cool them. Sounds as if that would be asking for transmission trouble.......all that strain...... Link to comment Share on other sites More sharing options...
JimD Posted August 20, 2008 Report Share Posted August 20, 2008 Sounds as if that would be asking for transmission trouble.......all that strain...... How does braking the the vehicle "strain" the transmission? Jim Drive your car. Use your cell phone. CHOOSE ONE ! Link to comment Share on other sites More sharing options...
Cadillac Jim Posted August 20, 2008 Report Share Posted August 20, 2008 Driving with the rear brakes partly applied shouldn't be any harder on the drive train than pulling a long grade. Of course, everything is a matter of moderation versus extremes... -- Click Here for CaddyInfo page on "How To" Read Your OBD Codes-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data -- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC Yes, I was Jims_97_ETC before I changed cars. Link to comment Share on other sites More sharing options...
KHE Posted August 20, 2008 Report Share Posted August 20, 2008 Nobody said anything about driving with the emergency brake locked up... the post was to accelerate to 45 MPH and use the emergency brake to slow down to 10 MPH and repeat 10 times. No strain on the trans...... Kevin '93 Fleetwood Brougham '05 Deville '04 Deville 2013 Silverado Z71 Link to comment Share on other sites More sharing options...
Bill4209 Posted August 20, 2008 Author Report Share Posted August 20, 2008 Driving with the rear brakes partly applied shouldn't be any harder on the drive train than pulling a long grade. Of course, everything is a matter of moderation versus extremes... Well I decided tp use the parking brake to slow down the car and see if this was the cause of my brake pedal pulsation.SURE ENOUGH my parking brake was pulsating as soon as I depressed it slightly.After several starts and stops the pulsation would not go away.I am going to replace the rear rotors and pads now after doing so on the front for no reason....Live and learn.... Link to comment Share on other sites More sharing options...
Bill4209 Posted August 20, 2008 Author Report Share Posted August 20, 2008 At least I didnt waste money on a mechanic to figure this out......Rear rotors and pads all along were bad....I even tried rotating tires myself... Link to comment Share on other sites More sharing options...
Bill4209 Posted August 20, 2008 Author Report Share Posted August 20, 2008 I even looked for loose tie rods,broken springs.bad shocks.nothing......All that time and effort and it was the rear rotors and or pads all along......SHEEEEEEEESH!!!!! Link to comment Share on other sites More sharing options...
jking220 Posted August 20, 2008 Report Share Posted August 20, 2008 I even looked for loose tie rods,broken springs.bad shocks.nothing......All that time and effort and it was the rear rotors and or pads all along......SHEEEEEEEESH!!!!! Yup... Lifes a B*tch. Think about all the money you would have wasted having a mech. check out/replace all of those things. Many mechs just want to throw parts at the car, esp. if it has alot of miles. You have to take the learning curve into account when you look at how much money you are saving when you work on your own car. Changing brakes may take all day the first time you do them, but they may only take an hour or so if you're familiar with them. Jonah Link to comment Share on other sites More sharing options...
KHE Posted August 20, 2008 Report Share Posted August 20, 2008 Have you mic'd the rotors? Maybe there is enough material to have them turned if you can find a place to do it for a reasonable amount of money. Kevin '93 Fleetwood Brougham '05 Deville '04 Deville 2013 Silverado Z71 Link to comment Share on other sites More sharing options...
Bill4209 Posted August 21, 2008 Author Report Share Posted August 21, 2008 Have you mic'd the rotors? Maybe there is enough material to have them turned if you can find a place to do it for a reasonable amount of money. No....I have already purchased new ones with pads that I will be putting on the car Friday..... Link to comment Share on other sites More sharing options...
lothos Posted August 21, 2008 Report Share Posted August 21, 2008 And it could be as simple as an uneven coating of brake pad material on the rotor. If that is the case, you might correct the problem by putting some serious heat into the rear brakes by using only the Park brake pedal to slow the car from 45 MPH to about 10 MPH several consecutive times (about 10 times should be good). Do not be concerned if you see smoke and can smell hot brake pads; that is what you want. Speed at 45 MPH and use Park brake down to 10 MPH, accelerate to 45 MPH and brake to 10 MPH. Repeat ten times. Park the car for an hour to allow the parts to cool; do not apply Park brake. Repeat if necessary. I have no experience with your year/model, so you are on your own to deal with the Park brake pedal latching arrangement. I've had some brake pulsing off and on that I assumed was caused by my bad ball joint or my front rotors. I tried braking with the emergency brake and got some pulsing. I tried what you suggested, and could smell hot brakes. Drove around on the freeway for 20 minutes or so to try and cool the pads and rotors. The procedure seems to have worked, and I don't really have any pulsing anymore. I'll keep watching it, I've only driven ten minutes to work since then. Free fixes are awesome, thanks JimD! WARNING: I'm a total car newbie, don't be surprised if I ask a stupid question! Just trying to learn. Cheers! 5% discount code at RockAuto.com - click here for your discount! Link to comment Share on other sites More sharing options...
JimD Posted August 21, 2008 Report Share Posted August 21, 2008 I've had some brake pulsing off and on that I assumed was caused by my bad ball joint or my front rotors. I tried braking with the emergency brake and got some pulsing. I tried what you suggested, and could smell hot brakes. Drove around on the freeway for 20 minutes or so to try and cool the pads and rotors. The procedure seems to have worked, and I don't really have any pulsing anymore. I'll keep watching it, I've only driven ten minutes to work since then. Free fixes are awesome, thanks JimD! It works more often than not. Certainly deserves a try before throwing money at the brakes. It is really quite difficult to warp an OEM class rotor. Jim Drive your car. Use your cell phone. CHOOSE ONE ! Link to comment Share on other sites More sharing options...
Bill4209 Posted August 28, 2008 Author Report Share Posted August 28, 2008 All 4 wheels now have new slotted rotors and ceramic pads.......Brakes like new money....Thanks fellas for all of the great clues.......Did everything myself..... Link to comment Share on other sites More sharing options...
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