Okay so goes like this, trucks front right was hanging up so I cleaned the retaining tabs for the pads and bled that caliper. Still did it so I put a new caliper and master cylinder on and bled all points till good clean fluid no bubbles. Now pedal is mushy and goes straight to floor when truck is running. I go drive it and I can't get it to lock up the tires with the pedal against the floor however when I cram them this hard a caliper sticks somewhere and the truck is terrible hard to get rolling again but will release after a few seconds. I've even gone as far as to pressure bleed them from the master cylinder and ran about three qts. through at all four points. What am I missing? Hydro boost and abs pump I havnt dicked with. Thanks for any help.
02 3500 brake pedal to the floor and mushy?
- Thread starter BigDMax05
- Start date
tech 2, snap on, and maybe a few other scanners can get into the trucks auto bleed. that will bring your pedel back out
Sometimes a brake hose can act like a check valve. Replace the hoses if they look old or cracked.
ive replaced both thinking the same things youve suggested. i got lucky when i ordered the master cylinder online they accidentally sent me 2 for 1 so i am gonna install the other one when i get time and try it.
Did you bench bleed the master cylinder before installing it? After I do a ABS bleed I like to bleed the brakes again just to make sure there is no air in the system.
A failed hydroboost will yield a similar feel to the peddle. I do plenty of them for low pedal concerns here at the shop. The auto bleed with the tech 2 will help some if you got excessively air bound in the lines from the master to the abs unit. If not there is not going to be air in the system. If you have used the power bleed system from a shop that should have forced the air out of the abs unit regardless.
Yes for about 20 minutes. I have not bled them after running the abs test.
I thought the same thing but I had pedal before I started dickin around with stuff. I pressure bled them also for awhile.
Changed the master cylinder last night to the other new I got. Bench bled until I had NO air bubbles and the plunger was stiff after about an 1/8" travel. Rebled the system at the calipers and now the pedal is worse than it was before. The master cylinder is good. I'm seriously thinking of putting a new hydra boost on it. Does anyone know on the abs pump internally how the valves operate. Almost wondering if a valve isn't stuck in the abs pump. I would doubt it but.......
how does your powersteering fluid look? does your steering seem any harder to turn than it used to? check power steering fluid, powersteering pump, hydrobooster, brake hoses.
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Well I finally figured this shit out. The master cylinder that I bought off of partsgeek.com was actually for a 6.0 gas truck with a vacuum booster instead of a hydroboost. Dang part# checked out right when I searched originally but was wrong part # when I searched for a 3/4 ton. I am so glad I got this crap figured out. Good news is my brake caliper hanging up is gone. Thanks for the replies and suggestions guys!
Yeah the bad thing was though that the damn master cylinders look identical. Had me scratching my head so damn bad it wasn't funny. I was actually about to crash the truck into a tree and collect the insurance money. Jk
There may be another solution to this, or related pedal feel. There is a site rhat has been referenced on DD before, so i will post this and if need be i understand why a mod would remove my post.
Killerbee. Killerbee duramax solutions. I can not even begin to come close to the explanation this man has researched, applied and informs as well as provides the hardware needed to overcome these manufacturer deficit's. One of his discoveries was that there is a spring, probably costs a couple dollars to replace, and even has diferant rates, for diferant driving styles, that goes behind the accelerator pedal. This info is founded on scientific research, check this guy out if you have not already. Who knows maybe all you need is a spring.
I recently foind out he will be unabailable until the end of the month, so if you try to make a purchase, or request a reply, it may take some time for a response. Fyi
Killerbee. Killerbee duramax solutions. I can not even begin to come close to the explanation this man has researched, applied and informs as well as provides the hardware needed to overcome these manufacturer deficit's. One of his discoveries was that there is a spring, probably costs a couple dollars to replace, and even has diferant rates, for diferant driving styles, that goes behind the accelerator pedal. This info is founded on scientific research, check this guy out if you have not already. Who knows maybe all you need is a spring.
I recently foind out he will be unabailable until the end of the month, so if you try to make a purchase, or request a reply, it may take some time for a response. Fyi