BodybyFisher Posted September 9, 2006 Report Share Posted September 9, 2006 BBF means Big Block Ford guys, maybe I better to go back to Scotty, By the way, if you do a search there is another BodybyFisher who is a member of a Chevy site...... and I thought I was being unique with BodybyFisher.... See him (not me) here: http://www.classicheartbeat.com/forums/member.php?userid=301 Pre-1995 - DTC codes OBD1 >> 1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/ Cadillac History & Specifications Year by Year http://www.motorera.com/cadillac/index.htm Link to comment Share on other sites More sharing options...
epricedright Posted September 9, 2006 Report Share Posted September 9, 2006 EPR means Electron Paramagnetic Resonance (EPR), also known as electron spin resonance (ESR) and electron magnetic resonance (EMR), is the name given to the process of resonant absorption of microwave radiation by paramagnetic ions or molecules, with at least one unpaired electron spin, and in the presence of a static magnetic field. EPR was discovered by Zavoisky in 1944. It has a wide range of applications in chemistry, physics, biology, and medicine: it may be used to probe the "static" structure of solid and liquid systems, and is also very useful in investigating dynamic processes. Yeah, that fits me well. Link to comment Share on other sites More sharing options...
pos2nat Posted September 9, 2006 Report Share Posted September 9, 2006 I would replace front calipers before looking at the booster. If there is unven frt pad wear and the rear brakes seem to be working more than the front, the frt calipers could be the issue. Link to comment Share on other sites More sharing options...
BodybyFisher Posted September 9, 2006 Report Share Posted September 9, 2006 My brakes have shown uneven wear also, with the leading edge wearing faster. The rubber bushings in the calipers MUST be replaced as they wear allowing the caliper to flop around or oscillate... Replace and properly lube the bushings they are available at the dealer Pre-1995 - DTC codes OBD1 >> 1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/ Cadillac History & Specifications Year by Year http://www.motorera.com/cadillac/index.htm Link to comment Share on other sites More sharing options...
epricedright Posted September 9, 2006 Report Share Posted September 9, 2006 My brakes have shown uneven wear also, with the leading edge wearing faster. The rubber bushings in the calipers MUST be replaced as they wear allowing the caliper to flop around or oscillate... Replace and properly lube the bushings they are available at the dealer As cheap as those rubber bushings are, it's silly not to replace them. Link to comment Share on other sites More sharing options...
BodybyFisher Posted September 9, 2006 Report Share Posted September 9, 2006 My brakes have shown uneven wear also, with the leading edge wearing faster. The rubber bushings in the calipers MUST be replaced as they wear allowing the caliper to flop around or oscillate... Replace and properly lube the bushings they are available at the dealer As cheap as those rubber bushings are, it's silly not to replace them. You'd be surprised they are not that cheap, the rear is more expensive than the front. If I recall the rear bushing (only one) and boots was in the $40 range maybe more.... OUCH, but I think they could be replaced every other pad change and you'd be OK... UNLESS, you have serious brake shudder, then I would replace them as they will wear faster from the vibration.... Pre-1995 - DTC codes OBD1 >> 1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/ Cadillac History & Specifications Year by Year http://www.motorera.com/cadillac/index.htm Link to comment Share on other sites More sharing options...
epricedright Posted September 9, 2006 Report Share Posted September 9, 2006 My brakes have shown uneven wear also, with the leading edge wearing faster. The rubber bushings in the calipers MUST be replaced as they wear allowing the caliper to flop around or oscillate... Replace and properly lube the bushings they are available at the dealer As cheap as those rubber bushings are, it's silly not to replace them. You'd be surprised they are not that cheap, the rear is more expensive than the front. If I recall the rear bushing (only one) and boots was in the $40 range maybe more.... OUCH, but I think they could be replaced every other pad change and you'd be OK... UNLESS, you have serious brake shudder, then I would replace them as they will wear faster from the vibration.... At rockauto, the Raybestos rear kit is $26.89 (for both sides), which includes all the rubber and clips for each side. The front kit for both sides (4 bushings) is $4.97. The front kit is a no brainer, I'd change every time. The rear ones I'd say every other time. I've done my fronts twice, and each time I have torn the front boots while removing them. I'm sure I wasn't as careful as I could have been, being I knew I was going to replace them, but I'd hate to be in the middle of the job and tear one and not have a new one on hand. Link to comment Share on other sites More sharing options...
BodybyFisher Posted September 9, 2006 Report Share Posted September 9, 2006 Agreed, I knew the front was cheaper, but I did not know how cheap they were. I still am shocked at that price. I believe I paid more, but if that is the price, terrific... I am doing my front brakes as we speak but I am not replacing them, (in my defense, I replaced the bushings in the last few months however, when I did my struts and springs, whew! Its also nice to once in a while ask a Firestone, Goodyear or the dealer what they charge for front and rear brakes to give you an actual point of reference, even with replacing everything including brake hoses (if you wanted to) you are saving money! Plus you avoid the cross selling of their revenue generators (sir your power steering needs flushing!) Pre-1995 - DTC codes OBD1 >> 1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/ Cadillac History & Specifications Year by Year http://www.motorera.com/cadillac/index.htm Link to comment Share on other sites More sharing options...
epricedright Posted September 9, 2006 Report Share Posted September 9, 2006 Agreed, I knew the front was cheaper, but I did not know how cheap they were. I still am shocked at that price. I believe I paid more, but if that is the price, terrific... I am doing my front brakes as we speak but I am not replacing them, (in my defense, I replaced the bushings in the last few months however, when I did my struts and springs, whew! Its also nice to once in a while ask a Firestone, Goodyear or the dealer what they charge for front and rear brakes to give you an actual point of reference, that even with replacing everything including brake hoses (if you wanted to) you are saving money! Plus you avoid the cross selling of their revenue generators (sir your power steering needs flushing!) And most importantly, to know they're being done RIGHT! You may have spent more on those bushings Mike. Those prices are for Raybestos products. The Delco's are more I'm sure. My first set were Ray's, but I bought my last set of front bushings from partszoneonline and they were Delco's and I believe they were $9 for the set - but don't quote me on that price. Too lazy to find my receipt, and they don't list them online. I wish I would have made a spreadsheet like you have to track my repairs, cost and mileage/date when done, etc. One day maybe? Next car for sure! Link to comment Share on other sites More sharing options...
jfreezn Posted September 10, 2006 Report Share Posted September 10, 2006 The brakes in my 96 Deville DO NOT work very well. The pedal has always felt kind of spongy, ever since I owned it (purchased ~ 90K miles). The car has 150K miles on it. I do all my own work on the car. I changed the rear pads and rotors at 110K then the front pads and rotors at 115K miles. At that point I decided to use cross drilled/slotted rotors and ceramic brake pads (FRONT ONLY). I have bled and flushed and bled and bled the brakes many, many times. I have followed the procedure in the manual for bleeding. LF, RF, LR, RR. I have had a helper with the bleeding process, I have even used a pressure bleeder. I just cannot get a firm pedal. Heres what happens when I try to brake the car hard. The car stops but its not exactly like the ABS has to even pulse. Heck, my body weight isn’t even thrown against the seat belt. I can’t even go through a full bedding procedure without the car’s brakes getting even more spongy. If I try to stop hard from 30mph a couple times then the pedal will almost go to the floor after even 2 stops. …. But the rear brakes seem to be working much harder than the front. They will even smoke from using them so hard during a couple hard braking procedures, as in a brake bedding procedure. So after having lived with these spongy, not so great brakes I decided to do something about it this week. I figured it HAD to be the front brake pads. I’ve got a set of cross drilled/slotted rotors, but my 20 year old 4000# truck will stop way before this car will. I picked up a set of semi-metallic titanium pads and proceeded to change the front. I even changed both front flexible hoses then bled the entire system, including the master cylinder, just as the Helms manual tells you how to. But guess what, I still have the same spongy feeling in the pedal. The system does not have any leaks as the level in the master cylinder never drops, so I am really at a loss as to what causes this lack of brake performance. When I bleed the brakes there is no air left coming out of the bleeders. I do not think the fronts are working as hard as they should. Some items of concern I had when changing the front pads were the abnormal wear they had. The inner pads had significantly more wear than the outer. It was a very abnormal wear as the inside of the inner pad was worn significantly but the outer edges were not. It only seemed to wear where the piston was pushing it against the rotor. Weird… but I thought I’d mention it anyway. I know some of you will come back with suggestions to change the bushings, but I don’t see a need to as I liberally coated the inside with grease and was able to push the pins into the bushings by hand… easily too to note. So can you guys help me out with this one. The bottom line is: The brake pedal is spongy, it gets even more spongy with hard braking, the car doesn’t stop worth a darn, the brakes have been bled, bled and bled again. So what to do… I’m at a loss!!!!! The master cylinder has two pressure systems in it. I am betting that one of them is bad, probably damaged from using the brake pedal to bleed the brakes. If you do not put a block under the brake pedal, your helper will push the pedal all the way to the floor, causing the the pistons to travel into an unused, and often rough area of the master cylinder. this tears the seals up and you loose some or all of your braking, yet there is no external leakage. I do not know if your master cylinder is piped front with front or left front with right rear (chriscrossed) but it really sounds like you have lost your front brakes, which normally do over 60% of the braking. CHANGE THE MASTER CYLINDER and never bleed a USED master cylinder with the pedal again! Lives depend on it! Regards Jim in Phoenix Jim in Phoenix Link to comment Share on other sites More sharing options...
KHE Posted September 10, 2006 Report Share Posted September 10, 2006 I have not verified that any of the brake lines are leaking. Nothing is visible... but I have not done a thorough inspection taking the time to physically verify each and every inch of them. I did remove the master cylinder and notice that there is some brake fluid on the power booster. So perhaps the MC is leaking some fluid on the Power booster. Replacing the MC is my next step. I just sent an email to Brasington requesting a price for one. We'll see what they come back with. The other option is to get one from Advance Auto. They have a new Bendix for $140 and a Raybestos for $315. The brake fluid leakage on the booster is a sure sign that the master cylinder is shot. Kevin '93 Fleetwood Brougham '05 Deville '04 Deville 2013 Silverado Z71 Link to comment Share on other sites More sharing options...
BodybyFisher Posted September 10, 2006 Report Share Posted September 10, 2006 The brakes in my 96 Deville DO NOT work very well. The pedal has always felt kind of spongy, ever since I owned it (purchased ~ 90K miles). The car has 150K miles on it. I do all my own work on the car. I changed the rear pads and rotors at 110K then the front pads and rotors at 115K miles. At that point I decided to use cross drilled/slotted rotors and ceramic brake pads (FRONT ONLY). I have bled and flushed and bled and bled the brakes many, many times. I have followed the procedure in the manual for bleeding. LF, RF, LR, RR. I have had a helper with the bleeding process, I have even used a pressure bleeder. I just cannot get a firm pedal. Heres what happens when I try to brake the car hard. The car stops but its not exactly like the ABS has to even pulse. Heck, my body weight isn’t even thrown against the seat belt. I can’t even go through a full bedding procedure without the car’s brakes getting even more spongy. If I try to stop hard from 30mph a couple times then the pedal will almost go to the floor after even 2 stops. …. But the rear brakes seem to be working much harder than the front. They will even smoke from using them so hard during a couple hard braking procedures, as in a brake bedding procedure. So after having lived with these spongy, not so great brakes I decided to do something about it this week. I figured it HAD to be the front brake pads. I’ve got a set of cross drilled/slotted rotors, but my 20 year old 4000# truck will stop way before this car will. I picked up a set of semi-metallic titanium pads and proceeded to change the front. I even changed both front flexible hoses then bled the entire system, including the master cylinder, just as the Helms manual tells you how to. But guess what, I still have the same spongy feeling in the pedal. The system does not have any leaks as the level in the master cylinder never drops, so I am really at a loss as to what causes this lack of brake performance. When I bleed the brakes there is no air left coming out of the bleeders. I do not think the fronts are working as hard as they should. Some items of concern I had when changing the front pads were the abnormal wear they had. The inner pads had significantly more wear than the outer. It was a very abnormal wear as the inside of the inner pad was worn significantly but the outer edges were not. It only seemed to wear where the piston was pushing it against the rotor. Weird… but I thought I’d mention it anyway. I know some of you will come back with suggestions to change the bushings, but I don’t see a need to as I liberally coated the inside with grease and was able to push the pins into the bushings by hand… easily too to note. So can you guys help me out with this one. The bottom line is: The brake pedal is spongy, it gets even more spongy with hard braking, the car doesn’t stop worth a darn, the brakes have been bled, bled and bled again. So what to do… I’m at a loss!!!!! The master cylinder has two pressure systems in it. I am betting that one of them is bad, probably damaged from using the brake pedal to bleed the brakes. If you do not put a block under the brake pedal, your helper will push the pedal all the way to the floor, causing the the pistons to travel into an unused, and often rough area of the master cylinder. this tears the seals up and you loose some or all of your braking, yet there is no external leakage. I do not know if your master cylinder is piped front with front or left front with right rear (chriscrossed) but it really sounds like you have lost your front brakes, which normally do over 60% of the braking. CHANGE THE MASTER CYLINDER and never bleed a USED master cylinder with the pedal again! Lives depend on it! Regards Jim in Phoenix Very Good Jim... That would explain why I have experienced bad master cylinders after doing a brake job with bleeding the brakes.. Having rebuilt a few the unused area can contain rust and pitting, so you are right about the seals not really sealing good. I would imagine that if you put your foot on the pedal with constant force, the pedal would sink also. Pre-1995 - DTC codes OBD1 >> 1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/ Cadillac History & Specifications Year by Year http://www.motorera.com/cadillac/index.htm Link to comment Share on other sites More sharing options...
boatboy Posted September 10, 2006 Author Report Share Posted September 10, 2006 Jim - The front brakes have never been good .... but now that I think back, they probably started to deteriorate after I did my first brake job... probably from bleeding w/ the brake pedal. So from now on, I will definitely place a phone book or something underneath the pedal when bleeding w/ such. Hopefully the master cylinder will fix the spongy pedal... then I'll work on the uneven brake wear. I'll definitely be replacing the bushings and using silicone grease from now on. I'm not so sure I have in the past. I'm so glad that "someone" on here mentioned that. Just kidding BBF. Thanks!!! ...oh another thing to add.... I have NEVER had to add any fluid to the master cylinder! Link to comment Share on other sites More sharing options...
zonie77 Posted September 10, 2006 Report Share Posted September 10, 2006 Stuck calipers will give a spongy feel as you are forcing them to move against a strong resistance. They move but you don't get the force against the rotor you want. The leak at the rear of the master needs to be addressed also. I might suggest doing them seperately so you can tell which fixes the problem. The master needs to be changed either way so do it first but I'm pretty sure it won't completely fix the spongy pedal. Link to comment Share on other sites More sharing options...
Ranger Posted September 10, 2006 Report Share Posted September 10, 2006 If you do not put a block under the brake pedal, your helper will push the pedal all the way to the floor, causing the the pistons to travel into an unused, and often rough area of the master cylinder. this tears the seals up I have never heard that before, nor expirienced it. It makes a good case for vacuum bleeding though. Link to comment Share on other sites More sharing options...
BodybyFisher Posted September 10, 2006 Report Share Posted September 10, 2006 Jim - The front brakes have never been good .... but now that I think back, they probably started to deteriorate after I did my first brake job... probably from bleeding w/ the brake pedal. So from now on, I will definitely place a phone book or something underneath the pedal when bleeding w/ such. Hopefully the master cylinder will fix the spongy pedal... then I'll work on the uneven brake wear. I'll definitely be replacing the bushings and using silicone grease from now on. I'm not so sure I have in the past. I'm so glad that "someone" on here mentioned that. Just kidding BBF. Thanks!!! ...oh another thing to add.... I have NEVER had to add any fluid to the master cylinder! I am not sure what you are kidding about, unless you are implying that I should have mentioned that the bushings be replaced sooner. The bushings are not causing your front to rear problem, but they may cause your pads to wear uneven front to back or allow caliper to oscillate, but they are not causing your problem. The inside pad wearing faster than the outside pad is an indication that the sliders were frozen. What did you find when you pulled the sliders were they stuck? The stainless steel sliders come out of the bushings and they are cleaned and greased with high temp silicone caliper grease. Are yours free? See scan below As you may or may not know, these threads are brainstorming sessions. Solutions to the problem come out as the problems are discussed and we dive deeper into the problem. We have gone on for pages and pages before a problem is solved. Your post was EXTENSIVE to say the least and covered many issues, and the thread tends to follow a certain course. I felt that MAC covered the gamit of problems including the faulty proportioner valve. I was thinking? What would cause the REAR to smoke, and the FRONT NOT pick up its share, ESPECIALLY given that the FRONT does the majority of the braking... You bleed it good, changed the hoses. It was looking like master cylinder to me, the booster would affect the entire system not just the front. Check this link for interesting information http://www.automotiveforums.com/vbulletin/...ad.php?t=151792 Do you recall when you bled it, if the fluid came out slower in the FRONT than it did in the REAR? Pre-1995 - DTC codes OBD1 >> 1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/ Cadillac History & Specifications Year by Year http://www.motorera.com/cadillac/index.htm Link to comment Share on other sites More sharing options...
epricedright Posted September 10, 2006 Report Share Posted September 10, 2006 Zonie, I was wondering the same thing, but I was more interested in helping fix the spongy pedal first..they appeared to be two different problems. Boatboy, did you use silicone grease and not petroleum grease for your slider pins? The pins will slide at first with petroleum grease, but will later cause the boots to swell and will seize on the pins. Something is hanging up causing your pads to wear unevenly. I had to use a dremel tool and a wire brush attachment on my drill to clean up the contact/sliding areas (rust and uneven high spots) where the calipers slide on the knuckle. I even put a dab of grease in spots. If that's not it, then I would suspect the caliper bore is rusted and the piston is sticking. I would be sure and check your calipers and make sure they're not leaking before replacing your master cylinder, although if you're leaking at the MC, then it definately needs to be replaced. Jim - The front brakes have never been good .... but now that I think back, they probably started to deteriorate after I did my first brake job... probably from bleeding w/ the brake pedal. So from now on, I will definitely place a phone book or something underneath the pedal when bleeding w/ such. Hopefully the master cylinder will fix the spongy pedal... then I'll work on the uneven brake wear. I'll definitely be replacing the bushings and using silicone grease from now on. I'm not so sure I have in the past. I'm so glad that "someone" on here mentioned that. Just kidding BBF. Thanks!!! ...oh another thing to add.... I have NEVER had to add any fluid to the master cylinder! If you're using petroleum grease (hi temp or not), and not silicone grease, then that is a definate suspect for your uneven pad wear. I have seen first hand what petroleum grease does to those bushings. The petroleum eats at the rubber and will actually cause it to swell. Your bushings have SEIZED around your slider pins and is not allowing your caliper to "float" the pads away from your rotors. That would cause your brakes to overheat as well, and may make your fluid boil, which could contribute to your soft pedal. I'm surprised you don't have any brake shudder. See what "someone" wrote above about the SILICONE. I get no respect, none I tell ya. Back to poker for me. Regardless, if your master cylinder is leaking, replace it. Link to comment Share on other sites More sharing options...
zonie77 Posted September 10, 2006 Report Share Posted September 10, 2006 Not a lot of MC's have that rough area but I wrecked 3 before I realized what was happening when I ran into it. Good thing Autozone didn't know I was doing it! Too bad jfreezn wasn't around that day! Link to comment Share on other sites More sharing options...
adallak Posted September 10, 2006 Report Share Posted September 10, 2006 I never could get my brakes right.. th epedal is spongy and the braking distance is definitely longer that it's supposed to be. The saddest thing in life is wasted talent Link to comment Share on other sites More sharing options...
boatboy Posted September 10, 2006 Author Report Share Posted September 10, 2006 Are you losing brake fluid, I did not pick up on that in the prior posts? That is an entirely different story. I don't believe you stated you needed to add fluid. Sometimes as someone mentioned above the MC can leak at the rear, into the booster and the fluid can be sucking into the engine vacuum system. If you see fluid at the rear its possible you have seepage. Great...Now I'm just a "someone". Sorry BBF I should have directed that at epricedright. My bad!!! Yes, you are definitely right about these threads being brainstorming sessions. This has been a great thread. I've learned a lot about brakes from this thread alone. I'm attaching a few pics. This is my first attempt so bear with me. Here is a great example of uneven brake wear. You can see how the inside of the pad is worn significantly more than the outside. The inside pad is also worn much more than the outside pads. Obviously you can tell by my pics that I've used petroleum grease in the past. Where does one get silicone grease? Link to comment Share on other sites More sharing options...
adallak Posted September 10, 2006 Report Share Posted September 10, 2006 Good pictures. I never saw anything like that, what a strange pattern. The saddest thing in life is wasted talent Link to comment Share on other sites More sharing options...
boatboy Posted September 10, 2006 Author Report Share Posted September 10, 2006 Do you recall when you bled it, if the fluid came out slower in the FRONT than it did in the REAR? I do not recall if the fluid came out slower in the front than rear... The same from what I remember... but I didn't pay close attention to it. Link to comment Share on other sites More sharing options...
epricedright Posted September 10, 2006 Report Share Posted September 10, 2006 Good pictures. I never saw anything like that, what a strange pattern. The backing plates look like they're bent/warped. I would guess they were overheated due to the slider pins being seized, and actually warped. I imagine they've been red hot at times. I bet he's had terrible gas mileage lately as well. Again, I suspect the calipers are not sliding due to petroleum grease being used in the rubber bushings, causing the slider pins to actually seize in the bushings. That caused the brakes to overheat, which resulted in the brake fluid actually boiling, which subseguently caused increased pedal travel and made the brakes feel "spongy". I would replace the bushings, you may need to hone the bore where the bushings go if its rusty, make sure all sliding/contact areas between the caliper, pads and knuckle are clean with no rough/high spots, inspect the pins for pitting and clean (replace if necessary), grease the pins/bushings with Silicone brake grease, replace the leaking master cylinder, then power bleed the brakes with all new correct fluid using the method prescribed in the FSM. Hopefully the calipers and rotors are still OK and haven't been affected by this overheating. I would guess the rotors might need a clean up cut. I would be very surprised if they don't have pad deposition or warpage. Being the were cross drilled certainly helped them keep cooler. Interesting article: http://autos.yahoo.com/maintain/repairqa/b.../ques009_6.html "As the fluid soaks up moisture, it thickens and becomes less able to withstand heat and corrosion. The result is a significant drop in the fluid's boiling temperature, which may under the right conditions allow the fluid to boil in the calipers. Once brake fluid turns to vapor, the bubbles cause an increase in the distance the pedal must travel to apply the brakes. This condition should not be confused with "brake fade" that occurs when the brake linings get too hot as a result of prolonged braking. Brake fade requires greater and greater pedal effort to stop the vehicle while fluid boil increases pedal travel and makes the pedal feel soft or mushy." I never thought about this: "Air enters every time the fluid reservoir is opened (a good reason not to do so unnecessarily)." Makes sense. Link to comment Share on other sites More sharing options...
Patrick7997 Posted September 10, 2006 Report Share Posted September 10, 2006 Good pictures. I never saw anything like that, what a strange pattern. The backing plates look like they're bent/warped. I would guess they were overheated due to the slider pins being seized, and actually warped. I imagine they've been red hot at times. I bet he's had terrible gas mileage lately as well. Again, I suspect the calipers are not sliding due to the wrong grease being used in the rubber bushings, causing the bushings to seize the slider pins, which has caused the brakes to overheat, resulting in the brake fluid actually boiling, which subseguently causes increased pedal travel and makes the brakes feel "spongy". I would replace the bushings (grease with silicone brake grease), replace the pads, replace the leaking master cylinder, then power bleed the brakes with all new fluid using the method prescribed in the FSM. Hopefully the calipers and rotors are still OK and haven't been affected by this overheating. Look at this article: http://autos.yahoo.com/maintain/repairqa/b.../ques009_6.html "As the fluid soaks up moisture, it thickens and becomes less able to withstand heat and corrosion. The result is a significant drop in the fluid's boiling temperature, which may under the right conditions allow the fluid to boil in the calipers. Once brake fluid turns to vapor, the bubbles cause an increase in the distance the pedal must travel to apply the brakes. This condition should not be confused with "brake fade" that occurs when the brake linings get too hot as a result of prolonged braking. Brake fade requires greater and greater pedal effort to stop the vehicle while fluid boil increases pedal travel and makes the pedal feel soft or mushy." Exactly. Those pads are something else.... but the unevenness, as Epriced says, is because it wasn't sliding. It has to slide to work.... Don't put the front's back together until the calipers slide real nice.... the grease is called "Sil-Glyde" at NAPA, part #765-1351... but if you just ask for the silicone grease for a brake job, anyone will probably sell you the right stuff... then move on to the master cylinder... This has been a very educational thread. I never heard of the phone book under the brake pedal, but it makes sense.... but then, I have the vacuum pump thing that I use to bleed, so I never did the pump the brake pedal deal.... the magazine guys all seem to have the pump, so that's what I did.... Epriced also makes a good point about the heat.... I might be mentally preparing myself for a caliper rebuild, as well.... you're betting your life on these brakes.... make darn sure they're right in a parking lot before you go back on the road..... The Sil-Glyde is also excellent around door seals, trunk seals, window seals.... smear it on lightly, it'll keep those seals nice & supple.... I do that every fall, before I put the car away for the winter.... Link to comment Share on other sites More sharing options...
epricedright Posted September 10, 2006 Report Share Posted September 10, 2006 the grease is called "Sil-Glyde" at NAPA, part #765-1351... but if you just ask for the silicone grease for a brake job, anyone will probably sell you the right stuff... then move on to the master cylinder... Don't be surprised if many auto parts store personnel don't know to use Silicone grease for brakes. The first time I did my brakes, I went to Pepboys and asked for some grease to do my brakes, and they gave me regular petroleum high-temp grease. I used it and before I could finish the job, I noticed the pins were seized. They were nice and greasy and slid free at first. I then read my FSM and saw the mention of silicone. I then went back to Pepboys, pissed off they sold me the wrong grease, and even the manager there had no clue that petroleum grease could not be used for brakes with rubber bushings. He had no clue what I was talking about. I was in shock! To make matters worse, they do not even keep the silicone brake grease in the same area as the other grease. They had it hidden on the counter in small packets for a $1.00. I guess they were afraid of people stealing it, being they were so small. Btw, if your bushings are ever contaminated with petroleum grease, don't try to re-use them....throw them away as they are ruined...learned that the hard way. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.