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Tune, resistors and tcc

Man, that brake fluid looks like a mug of Army coffee!

Something's not right, you're getting contamination into your system from somewhere, could very well be deteriorating brake hose(s) or seals, either caliper/wheel cylinder or master cylinder. That fluid should still be nearly perfectly clear.
 
x2 on something isn't right. if you recently flushed it and refilled it looks like there is a leak somewhere and deteriorating rubber in the system. if you haven't already done so, I'd recommend replacing both front caliper hoses and the rear center hose. then pull your rear drums and inspect the wheel cylinders for any seepage around the boots. sometimes you'll never see a leak in that area due to water washing it off but if you gently pry off the dust boot and fluid comes out of the end if the wheel cylinder, there bad and in need of replacement. wheel cylinders and hoses are not an expensive repair.

just be sure to get the right ones. mine has a single rear wheel but with 8000 gvwr it requires the same wheel cylinders as a dually. found that out from a visit to the dealer. auto parts stores list the smaller ones for my truck only.
 
something else comes to mind. dragging brakes cooking the fluid will cause that dark color. first things that cause this is the rubber hoses. but like you say both front and rears are possibly dragging, it may be the MC causing this
 
Bad piston seals (not the dust boots) in the calipers can cause this, as well as your front brake dragging issues. As you apply the brakes, the caliper piston moves forward and the piston seal rocks forward slightly with the minute travel of the piston in the bore as the pad contacts the rotor. When you release the brake pedal, the pressure is removed from the piston and the seal will return back to its original position moving the piston back with it, this is a movement of only a few thousandths of an inch. If the seal has hardened with age, was installed wrong in its seat in the caliper piston bore or damaged during installation/assembly it can cause the piston to hang up in the apply position after the brake pedal has been released and that will cause dragging of the pad against the rotor. If damaged or hardened a seal can also cause the piston to "cock" slightly in the bore and remain "locked" in the apply position causing the pads to drag on the rotor after releasing the brake pedal. This can also occur if the caliper piston bore was honed and an oversized piston and appropriate seal weren't used and the original piston and standard seal reused, the piston can hang up in the bore. The same thing can happen with the rear wheel cylinders, too.

Do you have any idea what the idiot who did your "brake job" actually did to your brake system, @Stoney, besides majorly FUBARing up that one steel rear brake line and cobbling together a "fix" instead of just replacing it? Because if he tried to rebuild the calipers and messed up the seal and piston install, there could be the answer to almost all your issues.
 
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Sadly, he replaced the rear brake shoes, hardware, wheel cylinders,and drums.. replaced the calipers and front pads..
Of course this has all been done again 2-3 times since then... Me and a friend also replaced all 3 rubber hoses... Have also changed hydro boost and master cylinder a couple times ( kept getting leaks)... Have replaced power steering pump twice...
Chances are that all the parts are crap cause they all came from AutoZone.. so no telling what could be defective. No clue if he got air in abs.. 😟
 
Well, you know the general consensus of all the serious wrenchers on here about AZ and their parts - any kind of parts.

When it comes to brake parts I will only use new, OEM or aftermarket upgraded calipers or name brand remanufactured calipers (like Raybestos, Borg Warner or AC Delco) as there's too much on the line to use housebrand chainstore parts or generic.
 
I completely agree. Just not sure what to do now.. I bought them at the time cause they were what I could afford, if I remember right for drums shoes hardware wheel cylinders, ...rotors, pads, calipers (remember it's a dually) I believe it was close to a grand all in.. but not 💯 sure..
So now I'm stuck in the situation of I need to replace all of it with better quality.. which I can get my money back from these cause everything is lifetime warranty... BUT I have to do it all at once cause if I don't then I risk new parts getting f'ed up by old parts if I only do it a Lil at a time... So gotta get the money to buy all of it at once and pray I don't run into any problems cause once the trucks apart I can't get anywhere till it's done...(no other vehicles) and parts stores are 8-10 miles away..I suppose I should get on rock auto and get a total for everything then see what I can come up with..
 
Something is definitely wrong to do that in such short period of time.
And it is scary because something major means instant brake failure is possible.

Revive your brake thread ONLY if it did not get derailed. Otherwise start a new one and include EVERY SINGLE detail you can in order to the best of your ability.
Do full pictures and videos if you can.

I hate to throw parts at anything without diagnosis first. Fluids included. But that black means either the fluid was burned, or contaminated. I would immediately flush that out 100% because I know that is the main means of transportation currently. That fluid is scary as hell being that bad while that new.
 
@Will L if I could find the brake thread I would. Lol ..I'm debating on if changing the rubber hoses, calipers, pads, rear shoes, and wheel cylinders will be enough. The drums and rotors I can't see how could make a difference ,since they never come in contact with the brake fluid. And change the one under sized brake line also. But I honestly don't think doing the brake parts is going to do much good.. remember I've changed them all multiple times since this issue started.. although I should have changed that undersized brake line one of those times...
The other 4 major components in the system are the abs box, hydro boost, master cylinder, and power steering pump.
What do we think the odds are of any of them being the culprit? Obviously the MC could be According to what y'all have said.
 
Husker6.5 said:
Well, you know the general consensus of all the serious wrenchers on here about AZ and their parts - any kind of parts.

When it comes to brake parts I will only use new, OEM or aftermarket upgraded calipers or name brand remanufactured calipers (like Raybestos, Borg Warner or AC Delco) as there's too much on the line to use housebrand chainstore parts or generic.
Click to expand...
@Husker6.5 out of those brands what's the recommendation?. And what brand hoses?...I'm assuming I can get all the parts from Rock Auto.
Does any know the correct part numbers for my truck? I know there's been problems with getting the right wheel cylinders cause chain store computers say it's the same one for srw and drw..
 
on the wheel cylinders ,there is a larger bore wc which is what you need. also measure the width of your rear shoes and then measure the width of the shoe surface are in the drums. they should match with maybe a 1/8 -1/4" difference.
 
@Stoney for brake parts for my 6.5s (and many other vehicles of other mfrs I have) I go with Wagner, Raybestos, Power Stop, Power Specialties, SSBC, or ACDelco for new or remanufactured brake components including hoses, lines, associated hardware (like boots/seals, slider pins, pad springs/clips, etc).

Also, I'm assuming that when you did the calipers/pads you used new slider pins (the updated one piece, not the trouble-prone OEM pin and sleeve style), pad return springs, and the O-ring seals.

With the hydroboost unit, it is important that it has the right accumulator and pedal pin on it. The pedal pin is crucial, if it's too long it would retain pressure on the MC piston, which would cause pads/shoes to drag when the brake pedal is released.
 
Warped rotors drag every rotation.
Same for out of round drums.
where the caliper slides is a frequent place that if uneven a brand new perfect caliper will drag.

brakes are like engine or any other sub section- diagnose with time and sometimes special tools, or if you use the parts cannon it may take every single part.

imagine it is the slide on the right front caliper mount. Change everything except that and the problem will be the same. Some people change master cylinder 3 times. Or- Change all those parts and what if 1 is a new-defective part. Now the original problem is still there but a new one in the mix. Then eventually you change the original problem but it doesn’t make the system work right because the good booster you replaced with the defective new one is creating problems also.

Either replace every part like a restoration, or only replace known problems.

your fluid is toasted- literally. Replace it. Then if problem is there, in this situation you need in line pressure gauge to record what happens at each wheel. The most effective set up uses 2 electric sensor and records it while you see it on a screen. Hard to get those kits because $$$. Using a temp gun to check each caliper and drum after a drive going easy, another medium another hard. This sometimes can see what is happening.
If a brake is dragging and that is causing the fluid to burn- there ya go.

Or if master cylinder, wheel cylinder, caliper, prop valve, abs is breaking down and the ‘rubber’ from those part is turning it black that fast- checking pressure at all points can maybe help determine that. Not always though. Sometimes disassembly and inspect is the only way.
 
dbrannon79 said:
on the wheel cylinders ,there is a larger bore wc which is what you need. also measure the width of your rear shoes and then measure the width of the shoe surface are in the drums. they should match with maybe a 1/8 -1/4" difference.
Click to expand...
Yeah, IIRC the drum widths are the same and the difference is in the shoe width, the SRW being like an inch narrower than the drum, the DRW shoe the full drum width. The nice thing is that Rock Auto does show all the differences between 3500, 3500 DRW and 3500HD DRW applications for both the front disc and rear drum brakes.
 
Was looking at rock auto...they have reman AC Delco calipers, the hoses aren't bad prices..
Another thing I noticed..the other day I checked power steering fluid it was really low.. the steering usually feels ok but at times can be a little choppy or feel like power steering not working good . But that doesn't last it's intermittent..
Also (since power steering is part of the belt drive)..I can put a brand new belt on , tensioner sitting right in the perfect zone, and within 20 minutes of driving the belt is stretched and tensioner is at full extension like you'd expect with a worn out belt. Only mentioned it cause power steering pump is hooked to the hydro boost so I assume it all effects each other
 
Yeah, on mine at first I thought was weird, but after consulting with the dealer to get the RPO codes (glove box was missing when I bought the truck) even though mine was SRW it has the heavy 14 bolt floater rear axle with the same brakes as a dually. the wide shoes and WC's my door sticker shows 9000 GVWR (I think I mentioned 8000 before, I just had to go look to verify)

@Stoney on your ABS unit, is your ABS unit mounted on the side of the MC or the big one with the motors that's mounted on the inner fender (4 wheel unit) the proportioning valve is built into the one mounted on the fender. I had discovered that after I had done my brake job there is a pin under the rubber caps on each end of the valve. one side had popped out and I had to use a screw driver and push it back into place for my rears to start working correctly. the valve is designed to cut off the flow of fluid to the rear or front in the event of a pressure drop (leak) I have heard of these causing brake dragging also.
 
Stoney said:
Was looking at rock auto...they have reman AC Delco calipers, the hoses aren't bad prices..
Another thing I noticed..the other day I checked power steering fluid it was really low.. the steering usually feels ok but at times can be a little choppy or feel like power steering not working good . But that doesn't last it's intermittent..
Also (since power steering is part of the belt drive)..I can put a brand new belt on , tensioner sitting right in the perfect zone, and within 20 minutes of driving the belt is stretched and tensioner is at full extension like you'd expect with a worn out belt. Only mentioned it cause power steering pump is hooked to the hydro boost so I assume it all effects each other
Click to expand...

my belt and tensioner does the same thing. not sure why, but when I had replaced my belt as soon as I set it into place with the tensioner it looked perfect in the middle marks. crank it up and it immediately maxes out at the full tension stop. I never figured that one out. I think yours has a different pulley setup with the AC comp on the drivers side. mine has the pancake comp on the passenger side and the alt on the drivers side, tensioner next to the alt.
 
Mine has the big abs box on the inner fender..so if you do a brake job and Change callipers and wheel cylinders those pins in the abs will pop out cause if fluid pressure loss?? So they need to be reset when ever you change those parts? Do you by chance have a pic of them ?
 
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