Attention: TDR Forum Junkies 
Brake pedal goes down just below the level of the go pedal when I stop. The pedal doesn't really get hard unless I let off and re-apply. Then the pedal is hard and high and the truck stops better. Common thought - "air in the lines" - when I replaced the steel line between the frame and tank this past fall I also changed over to DOT4 5 fluid.
When I first did the brake line R&R and swaped fluids the pedal was like brand new (high and hard) then over the course of about a week it went back to the way it is now. I posted to the thread where I saw the DOT 4 5 fluid and it was suggested to bleed again and push the pedal slow to help get air out. I've been bleeding brake systems for 30 years or so (I always place a pedal stop - block of wood or 1/4 drive socket set box - under the pedal so the person manning the pedal doesn't push all the way to the floor and screw the master cylinder), but I'm never too old to learn something. So I figured I'd give the slow push method a try and used a clear hose on the bleeder - yep there was air in there - but, BINGO! the pedal was high and hard . . . for about a week.
What gets me is, when the pedal is "high and hard" and when it's not (and I push down then let off and push down again) the truck stops great! But, how things are now, if I don't give a pump then apply (just push down on the pedal) it doesn't stop as well. What worries me is on occasion wifey drives my truck, she used to be blond :-laf, and she takes my daughter with her usually too - not blond
- anyway you get the jest of my concerns here.
What could be going on? It's apparent that air is working it's way into the system, but where? The resevoir is dead on full and never low
could the air be getting in? RWAL device? or that funky little block up by the master cylinder/boost assy thingy-ma-giggy-gizmo? (with the red rubber cap on it) the block thing has a pin that pops out when the brake is depressed, and you're supposed to hold it up when bleeding the brakes (and of course I did each time)?
Gen info: I purchased a new 'frame to rear housing hose/line assy. ' that I plan to install in the spring. And, about 2 years back I installed the 3500 GMC wheel cylinders - seemed to help a little.
I'm stumped and have never had this before with this truck (owned since 01) or any other autos. I'm thinking air has got to be getting in where a logical entry way exists - the little block by the Mcylinder or the RWAL device both have items which move and which are tied to the fluid side of the systems????
- HELP!
When I first did the brake line R&R and swaped fluids the pedal was like brand new (high and hard) then over the course of about a week it went back to the way it is now. I posted to the thread where I saw the DOT 4 5 fluid and it was suggested to bleed again and push the pedal slow to help get air out. I've been bleeding brake systems for 30 years or so (I always place a pedal stop - block of wood or 1/4 drive socket set box - under the pedal so the person manning the pedal doesn't push all the way to the floor and screw the master cylinder), but I'm never too old to learn something. So I figured I'd give the slow push method a try and used a clear hose on the bleeder - yep there was air in there - but, BINGO! the pedal was high and hard . . . for about a week.
What gets me is, when the pedal is "high and hard" and when it's not (and I push down then let off and push down again) the truck stops great! But, how things are now, if I don't give a pump then apply (just push down on the pedal) it doesn't stop as well. What worries me is on occasion wifey drives my truck, she used to be blond :-laf, and she takes my daughter with her usually too - not blond
- anyway you get the jest of my concerns here. What could be going on? It's apparent that air is working it's way into the system, but where? The resevoir is dead on full and never low
could the air be getting in? RWAL device? or that funky little block up by the master cylinder/boost assy thingy-ma-giggy-gizmo? (with the red rubber cap on it) the block thing has a pin that pops out when the brake is depressed, and you're supposed to hold it up when bleeding the brakes (and of course I did each time)? Gen info: I purchased a new 'frame to rear housing hose/line assy. ' that I plan to install in the spring. And, about 2 years back I installed the 3500 GMC wheel cylinders - seemed to help a little.
I'm stumped and have never had this before with this truck (owned since 01) or any other autos. I'm thinking air has got to be getting in where a logical entry way exists - the little block by the Mcylinder or the RWAL device both have items which move and which are tied to the fluid side of the systems????
- HELP!
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