Im working on a 2004 chevy one ton cargo van 9600 gvw 70,000 miles ive replace all the rotors,pads,calipers,brake hoses,caliper mounts and hardware, it was all trash! When done the van seemed fine the after running in the city it started to pull left again, pedel up and down and some kind of pump noise running now and then. No anti lock brake light on and no codes in system? Im really lost guys anyone run into this before? thanks so much for this site and help. dan
van brake problems
- Thread starter littled55
- Start date
Sometimes the pins that the caliper slides on seize up. You might need to remove the sliding pins and boots and replace them. That happened to me and the truck would pull to one side. You can go under the van and try and slive the caliper with a screw driver and see if those pins are seized up or not. Just a suggestion.
paullud
Veteran Expediter
What do you make of the motor noises? I was thinking the motor is going bad and he is just getting the warning signs now.
Sent from my ADR6400L using EO Forums
chefdennis
Veteran Expediter
I am with Blizzard, there is a caliper hung/hanging up...the motor noise is the anti lock motor working because chances are the caliper is stuck appling brake pressure all the time without pedal pressure and when the brake pedal is applied, the anti lock wheel sensor is picking up a excess pressure and wheel lockup and is working as it should to eliminate it....
Pull the calipers, lube all the slides and pins...i am thinking the problem will go away....
Pull the calipers, lube all the slides and pins...i am thinking the problem will go away....
paullud
Veteran Expediter
I was getting the impression he was having the same problem before so that was why he put new calipers on. I thought the wheel sensors measured wheel speed not the pressure.
Sent from my ADR6400L using EO Forums
chefdennis
Veteran Expediter
my impression was hedid a brake job replacing everything because for the most part everything was junk...
and yes the wheel sensor does measure wheel speed but also wheel lockup....i use the excess pressure wording because a hung up caliper is already putting pressure on the rotor adding brake pedal pressure by appling the brake adds more pressure which can induce wheel lockup..
think of the anti brakes working when braking on ice..the wheel will lockup and slide..but the anti lock brake systen will engage the motor to actually pump the brakes in milliseconds releasing that lockup ...that what it is trying to do here with a hung up caliper...
and yes the wheel sensor does measure wheel speed but also wheel lockup....i use the excess pressure wording because a hung up caliper is already putting pressure on the rotor adding brake pedal pressure by appling the brake adds more pressure which can induce wheel lockup..
think of the anti brakes working when braking on ice..the wheel will lockup and slide..but the anti lock brake systen will engage the motor to actually pump the brakes in milliseconds releasing that lockup ...that what it is trying to do here with a hung up caliper...
Replacing all the hardware should include replacing the pins and using the included lube on the pins. If all this was done, then my guess would be a bad wheel bearing.
chefdennis
Veteran Expediter
a 2004 would have the sealed hub/bearing assemblies and while yes that could also cause petal pulsation, but they usually make a bunch of snap crackle and pop...and i wouldn't think theyd be bad at 70,000 unless those wheel were under water for day as the van sat in hub deep water in a flooded area....
cableguymn
Seasoned Expediter
I replaced tons of GM hubs before 70k I suspect this van has a binding piston in the caliper or a collapsed hose. lifted with wheel off give the brakes a good application with engine on. Then with no pressure on the peddle open the bleeder. If it shoots out there is a restriction in the hose, line or and pump. If it just trickles out try turning the rotor. It should be easy to turn.
also I have driven many of these that have a tendance to follow the road more than it should
Sent from my SGH-T769 using Tapatalk 2
also I have driven many of these that have a tendance to follow the road more than it should
Sent from my SGH-T769 using Tapatalk 2
You guys are great, the calipers came with the bolts,pins slides,and caliper mounts. Everything is new 1100.00 for parts alone not the cheap junk i wont deal with that crap. When spinning the hub one bearing is a touch loader then the other! My thinking is that a front wheel sensor is going bad and the abs pump is running? Is there a way to check these out? Or maybe the pump is bad? thanks again dan
chefdennis
Veteran Expediter
if it has a good pedal i wouldn't think bleeding the brakes would do much, but it is easy enough to do, so trying it would be too much to do....
i can't speak to replacing tons of those sealed hub/bearing assemblies, but the 3 trucks (2 of those 3500 CV's, all of them went passed 100,000 and the replacements over 150,000....but again, that doesnt mean its not a bad bearing...my Cargo Max has 118,000 on it right now, i was going to go 150,000 and replace them as a "preventive" deal, but more since i will be doing a bunch of maintainace at 125,000 and be oos to do it, chances are ill replace them then.
Even though all the hardware came with the new calipers, if you didn't lube the slides and the bolts, you could still have caliper hanging up...the anti lock wheel sensor / vane is part of the hub assembly....so to change it, you need to change the hub....and if you do 1 hub, do them both....for that van, youcan get good ones for about $85 a piece...and you already know how to get the rotor off the hub...
i can't speak to replacing tons of those sealed hub/bearing assemblies, but the 3 trucks (2 of those 3500 CV's, all of them went passed 100,000 and the replacements over 150,000....but again, that doesnt mean its not a bad bearing...my Cargo Max has 118,000 on it right now, i was going to go 150,000 and replace them as a "preventive" deal, but more since i will be doing a bunch of maintainace at 125,000 and be oos to do it, chances are ill replace them then.
Even though all the hardware came with the new calipers, if you didn't lube the slides and the bolts, you could still have caliper hanging up...the anti lock wheel sensor / vane is part of the hub assembly....so to change it, you need to change the hub....and if you do 1 hub, do them both....for that van, youcan get good ones for about $85 a piece...and you already know how to get the rotor off the hub...
This is kinda long but detailed.
TRY THIS FIRST Calipers off the shelf never have enough slide lube buy a small can of Permatex synthetic slide lube and brake cleaner clean the slides and boots then give them a happy dose of lube and work it into the slide they should slide verry easily.
Did you use new brake fluid? brake fluid is a heavy alcohol and has an infinity for moisture and they dont mix well you may have moisture in your fluid this can cause barke fluid to cavitate and brake failure if you used old fluid completely drain the fluid by opening the bleeder valves at all wheels and fill with new fluid. Even a little air in your lines will realy trip you up it can be in the pump even in the rear brake system especialy if you let the resivor go dry hydrolics are like that.
Start by looking near the proportioning valves for bleeders you may have an air pockett hiding if you cant find any bleeders or if theyre frozen shut gravity bleed the system by first compressing all brake calipers even the rear if you have rear disk brakes air likes to hide in the piston chambers drum brake wheel wheel cylinders typicaly flush out. Next open the bleeder valves at all wheels if the bleeder valves are rusted shut crack open the brake lines at the wheels and fill the master cylinder let gravity do your work for you untill you get a steady stream with no air bubbles at all wheels. When you have clear fluid at a steady stream with no bubbles usualy the drivers side front clears first close that wheel the front axle clears before the rear let gravity work untill all wheels are running clear fluid close each wheel as they clear. KEEP THE MASTER CYLINDER FULL DEFINITELY NO LESS THAN HALF FULL You will need at least a couple three quarts of fluid for most cars and light trucks buy more than you need. When all the wheels are clear have somone pump the brakes up and bleed the front drivers wheel first, then the front right then the rear closest to the feeder line first then the furthest out.
You usualy need to center the proportioning valves any time you open the brake lines or the master cylinder gets low or dry. Turn the key to the on position if your brake light comes on slowly pump your brakes untill your light goes out the valve should be centered. Start the van slowly pump the brakes if you pump too fast you can wreck some verry expensive dealer only parts. If the light comes back on shut the motor off you have at least two proportioning valves so you may need to repeat the centering process a couple few times. Keep your brake fluid full and only use fresh fluid especialy with anti lock systems.
NOTE Before going for a full brake fluid change try gravity bleeding and centering the proportioning valves If it dosent and you used old fluid work follow the whole process.
Also remember brake fluid dose an exelent job at removing paint especialy paint you dont want removed.
Good luck let me know how you make out.
Bob Wolf.
TRY THIS FIRST Calipers off the shelf never have enough slide lube buy a small can of Permatex synthetic slide lube and brake cleaner clean the slides and boots then give them a happy dose of lube and work it into the slide they should slide verry easily.
Did you use new brake fluid? brake fluid is a heavy alcohol and has an infinity for moisture and they dont mix well you may have moisture in your fluid this can cause barke fluid to cavitate and brake failure if you used old fluid completely drain the fluid by opening the bleeder valves at all wheels and fill with new fluid. Even a little air in your lines will realy trip you up it can be in the pump even in the rear brake system especialy if you let the resivor go dry hydrolics are like that.
Start by looking near the proportioning valves for bleeders you may have an air pockett hiding if you cant find any bleeders or if theyre frozen shut gravity bleed the system by first compressing all brake calipers even the rear if you have rear disk brakes air likes to hide in the piston chambers drum brake wheel wheel cylinders typicaly flush out. Next open the bleeder valves at all wheels if the bleeder valves are rusted shut crack open the brake lines at the wheels and fill the master cylinder let gravity do your work for you untill you get a steady stream with no air bubbles at all wheels. When you have clear fluid at a steady stream with no bubbles usualy the drivers side front clears first close that wheel the front axle clears before the rear let gravity work untill all wheels are running clear fluid close each wheel as they clear. KEEP THE MASTER CYLINDER FULL DEFINITELY NO LESS THAN HALF FULL You will need at least a couple three quarts of fluid for most cars and light trucks buy more than you need. When all the wheels are clear have somone pump the brakes up and bleed the front drivers wheel first, then the front right then the rear closest to the feeder line first then the furthest out.
You usualy need to center the proportioning valves any time you open the brake lines or the master cylinder gets low or dry. Turn the key to the on position if your brake light comes on slowly pump your brakes untill your light goes out the valve should be centered. Start the van slowly pump the brakes if you pump too fast you can wreck some verry expensive dealer only parts. If the light comes back on shut the motor off you have at least two proportioning valves so you may need to repeat the centering process a couple few times. Keep your brake fluid full and only use fresh fluid especialy with anti lock systems.
NOTE Before going for a full brake fluid change try gravity bleeding and centering the proportioning valves If it dosent and you used old fluid work follow the whole process.
Also remember brake fluid dose an exelent job at removing paint especialy paint you dont want removed.
Good luck let me know how you make out.
Bob Wolf.
paullud
Veteran Expediter
Brake fluid absorbs moisture and if not changed it can cause your brake fluid to boil and damage brake components.
Sent from my ADR6400L using EO Forums
Brake fluid is hygroscopic, which means it absorbs water and therefore the two do "mix". Water in brake fluid can significantly reduce the boiling point of brake fluid. Alcohol? Brake fluid martini? If the original poster has a brake hanging up, causing heat and the brake fluid is contaminated, lowering the boiling point, the vaporized moisture in the lines could cause the pulsating he described.
All new brake fluid and all slides work great! Went to my napa last night again to pick up the right front well bearing and it comes with the hub and anti lock censer also. this is all one asm so maybe with some luck thats my problem censer? will keep you guys informed. dan
chefdennis
Veteran Expediter
If you replace one side, id replace there other side also.....