F-150 brake problem (very strange ?)
03-21-2019, 09:48 PM
#1
F-150 brake problem (very strange ?)
2008 F-150 4x4
In the past week or so my brakes began to feel "spongy".
symptoms:
more or less every 3rd push or so on the brakes , the pedal went to the floor. Basically giving the feeling that the brakes were failing or almost failing. The next time I pressed on the brake pedal the it felt almost normal. And the same pattern has been repeating itself since then. No brake fluid leakage at all. Reservoir is full and remians that way. No fault alerts or codes of any kind have not showed up. Not even an ABS code, it is all clear.
servicing:
I has the brakes checked by a licensed mechanic. He decided to replace both front calipers units. No other problematic areas were picked up. He then took a fair amount of time to bleed the brakes (many times they were pumped up and then pressed full on....before they would "deflate"and go to the mat. Both the front and rear brakes on both sides (4) were bled to the max.. Again at no time was there any leakage of fluid anywhere and the forcing out of any lingering air pockets was achieved. I watch this myself actually. Nothing was replaced on the rear brakes, they were deemed fine.
result:
test drive seemed to be ok so I took that as a problem repaired. Not so fast ,not too long afterards while driving not so far awayaway the same problem has resumed. i.e. every 3rd dpress of the brakes as I use them when required, the brake pedal goes pretty much to the floor. Very concerning and alarming as you brake.
so i took the truck back again, a thorough inspection took place and another round of full bleeding and top of fluidup led to the next test drive. I let the mechanic drive, he was satisified they were working ok. So again I took that as problem repaired. Not all that long afterwards, the same recurring problem I had for the initial problem resumed. I pump up the brakes more than once just to see if that might help anything. No dice, my problem continues. That is -> when driving and then stopping, the first time the brakes are depressed they feel full (normal braking pressure). The second or third time they begin to lose some "strength", roughly half way deressed from the normal (which is the fully pumped up feel). And then the next time I depress the brake pedal almost goes to the mat. Again no fault alerts or codes are triggered.
Not sure what to do next? The only maintenance procedure that happened recently was the replacement of the drivers side front wheel bearing, close to 6+ weeks ago. All was fine brake wise up until about the 7 days. That's when this problem showed up and has remained since, even after being serviced twice.
I called the mechanic back and appears to be dumbfounded (imo). He mentioned something about an ABS pump, but haven't gone there yet and no ABS problems or codes have occurred.
Looking for help and an assessment of what might be happening and what I can do to get my brake pressure back to normal 100%.....that being EACH and EVERY TIME i depress the brakes. No brake fluid leakage anywhere has been detected.
help please..........strange !!
In the past week or so my brakes began to feel "spongy".
symptoms:
more or less every 3rd push or so on the brakes , the pedal went to the floor. Basically giving the feeling that the brakes were failing or almost failing. The next time I pressed on the brake pedal the it felt almost normal. And the same pattern has been repeating itself since then. No brake fluid leakage at all. Reservoir is full and remians that way. No fault alerts or codes of any kind have not showed up. Not even an ABS code, it is all clear.
servicing:
I has the brakes checked by a licensed mechanic. He decided to replace both front calipers units. No other problematic areas were picked up. He then took a fair amount of time to bleed the brakes (many times they were pumped up and then pressed full on....before they would "deflate"and go to the mat. Both the front and rear brakes on both sides (4) were bled to the max.. Again at no time was there any leakage of fluid anywhere and the forcing out of any lingering air pockets was achieved. I watch this myself actually. Nothing was replaced on the rear brakes, they were deemed fine.
result:
test drive seemed to be ok so I took that as a problem repaired. Not so fast ,not too long afterards while driving not so far awayaway the same problem has resumed. i.e. every 3rd dpress of the brakes as I use them when required, the brake pedal goes pretty much to the floor. Very concerning and alarming as you brake.
so i took the truck back again, a thorough inspection took place and another round of full bleeding and top of fluidup led to the next test drive. I let the mechanic drive, he was satisified they were working ok. So again I took that as problem repaired. Not all that long afterwards, the same recurring problem I had for the initial problem resumed. I pump up the brakes more than once just to see if that might help anything. No dice, my problem continues. That is -> when driving and then stopping, the first time the brakes are depressed they feel full (normal braking pressure). The second or third time they begin to lose some "strength", roughly half way deressed from the normal (which is the fully pumped up feel). And then the next time I depress the brake pedal almost goes to the mat. Again no fault alerts or codes are triggered.
Not sure what to do next? The only maintenance procedure that happened recently was the replacement of the drivers side front wheel bearing, close to 6+ weeks ago. All was fine brake wise up until about the 7 days. That's when this problem showed up and has remained since, even after being serviced twice.
I called the mechanic back and appears to be dumbfounded (imo). He mentioned something about an ABS pump, but haven't gone there yet and no ABS problems or codes have occurred.
Looking for help and an assessment of what might be happening and what I can do to get my brake pressure back to normal 100%.....that being EACH and EVERY TIME i depress the brakes. No brake fluid leakage anywhere has been detected.
help please..........strange !!
03-21-2019, 10:51 PM
#2
Senior Member
Im not a mechanic but it sounds like it might be something to do
with the booster which is vacum to engage your brakes watch this
if you will Hope it helps you
with the booster which is vacum to engage your brakes watch this
if you will Hope it helps you
03-22-2019, 11:22 PM
#5
Senior Member
you can look up parts here https://www.oemfordpart.com/auto-par...-v6-gas-engine when at site
change year and so on will give you close pricing and it must be one or the other master cyl. or booster
change year and so on will give you close pricing and it must be one or the other master cyl. or booster
03-23-2019, 12:12 PM
#7
Senior Member
like I mentioned Im not a mechanic...on this forum go to 2004 to 2008 f150 and you can ask their
also go on to youtube and type in something like * how to check master cylinder * *how to check
brake booster* hope one of these help you out ....where are you located
also go on to youtube and type in something like * how to check master cylinder * *how to check
brake booster* hope one of these help you out ....where are you located