Front brakes dragging

[jtrakel]

My passenger front brake is dragging pretty good when I spin the wheel vs the drivers side, the front end is in the air right now for some other work so I have not been driving the truck in some time. Brake fluid is pretty new from the previous owner (owned for about 4 months now) as he had to replace the caliper and rotor on the pass front brake because the rotor basically disintegrated while he owned it. This was discovered the day before I purchased the truck, the rotor, pads, and caliper all look brand new and have enough miles on them that the pads should be seated at this stage. When I am able to drive the rig I can smell the brakes after driving for a bit and a mixture of hard and normal brake applications, the pedal feels normal for a 20 year old truck so bleeding does not seem to be the issue in my mind at least.

 

Today I went ahead and backed off the bleed screws on the caliper until fluid was slowly seeping out, spun the wheel and no change to the amount of drag. With no pressure being applied in the system what else should I be looking at before I start throwing more parts at this truck (hub assy, new rotors, bend caliper bracket?) Appreciate any feedback, hopefully I'll have my PCM, ECM, and wiring harnesses for the transmission and engine back next week from Auto Computer Specialist so I can finally fire this thing up again!

 

I plan to take a video tomorrow of the difference between the two wheels and how they free spin, you can clearly hear the pads dragging on the passenger side.

[CUMMINSDIESELPWR]

piston is stuck in caliper. either rebuild or buy new.

[jtrakel]

10 minutes ago, CUMMINSDIESELPWR said:

piston is stuck in caliper. either rebuild or buy new.

 

I'm going to pull the caliper tomorrow and take a look. I like to believe it's operating correctly as it's only a few months old but many times over we have all seen a brand new part bad out of the box!

[Tractorman]

You may have a problem, or you may not.  At this stage I would not do anything with the brakes until I could drive the truck and make a better assessment.   The piston in the caliper moves very little when the brakes are applied and released.  When the brake pedal is released, the piston inside the brake caliper has no reason to move away from the rotor on its own.  So that means other forces have to be introduced to retract the piston slightly.  One of those forces is rotor runout which will push the piston slightly back into its bore, but that means truck has to be moving down the road for that to happen.  The other force is the square cut o-ring sealing the piston in the bore.  When hydraulic pressure is applied, the o-ring twists slightly as the piston forces the pad against the rotor.  When the hydraulic pressure is released, the square cut o-ring attempts to return to its original shape.  So, between the o-ring forces and rotor runout, the piston slightly retracts and removes the force against the rotor. 

 

When you park your truck in the garage, the last thing you do is step on the brake.  At this point any rotor may have a varying degree of drag, and not all rotors will have the same drag for the above stated reasons.

 

When you can, take your truck for a test drive.  Use the brakes only as much as needed.  After driving for awhile, pull off the road and check the temperature of each front rotor.  You can use your hand (carefully) or an infrared thermometer.  If you don't feel or see a major difference in temperature, then probably all is well.  If the passenger side rotor is much hotter than the driver's side, then you know you have a problem.

 

- John

Edited July 26, 2020 by Tractorman

[Mopar1973Man]

Another one I ran into is when people bleed the system when the fluid is nearly black in color typically push all the debris from the master into the bottom of the caliper and wedging up the pistons so they don't return properly. The calipers have to stay clean inside to keep the pistons moving freely. Another occurrence I've seen is heavy brake use (typically no exhaust brake installed) and heating the brake fluid till it scorches slightly causing the brake fluid to cake up on the pistons causing the brakes to drag too.

[jtrakel]

6 minutes ago, Mopar1973Man said:

Another one I ran into is when people bleed the system when the fluid is nearly black in color typically push all the debris from the master into the bottom of the caliper and wedging up the pistons so they don't return properly. The calipers have to stay clean inside to keep the pistons moving freely. Another occurrence I've seen is heavy brake use (typically no exhaust brake installed) and heating the brake fluid till it scorches slightly causing the brake fluid to cake up on the pistons causing the brakes to drag too.

 

All of the scenarios sound like a bad day, my fluid looks clear the the caliper is brand new. Not saying the PO couldn't have done something wrong because at this stage of my ownership with this rig anything is possible. I'm going to take what @Tractorman said and run the truck once it's operating again and go form there. I'm trying to not throw more parts at it but that 3rd gen brake upgrade looks like a good investment, would hate to purchase and install for the issue to still be present.

 

Still waiting on my ECM/PCM and wiring harness to be sent back from Auto Computer Specialist they've had my parts for well over a month now, found lots of issues so hopefully this truck will finally get itself in line so I can drive it across the country in September! The wife wants to do a 4,000 mile zig zag across the US back to Washington, i'm not looking forward to this at all  

Edited July 28, 2020 by jtrakel

[Mopar1973Man]

11 minutes ago, jtrakel said:

I'm trying to not throw more parts at it but that 3rd gen brake upgrade looks like a good investment, would hate to purchase and install for the issue to still be present.

 

Don't bother with 3rd Gen. Look towards a exhaust brake. Way better brake life at over 200k miles and going. 3rd gen might be a bigger caliper and clamping but wear is going to be the same. Exhaust brake if used properly you can do 95 to 99% of your stopping without ever touching the brake but below 20 MPH. This will reduced brake wear greatly. It might be a big one time purchase but the exhaust brake technically doesn't wear out. I've had my exhaust brake since 23k miles still going at 417k miles. My last set of rear pads where so old that the road salt rotted the pad off the backing plate and still 75% of pad left. 

Edited July 28, 2020 by Mopar1973Man

[CUMMINSDIESELPWR]

coming down the big hill on i70 in colorado from the mountains to denver, i can set the ex brake and cruise to whatever speed i want and it will modulate itself at that speed the whole way down severe grades with no touching of brakes at all if no traffic is stopping me.

 

get an exhaust brake

 

[Mopar1973Man]

Yup. Exactly. I allow my throttle to modulate the exhaust brake and control the speed.

 

This is why I will not suggest the 3rd gen brakes. You get slightly larger pad and rotor but done nothing to aid in actual speed control 3rd gen brakes still get hot if you use the service brake to control speed. But with a exhaust brake you can control your speed so you never touch the service brakes. Several people out did the same thing for all the long canyon roads and needlessly to say does no good still get the brakes hot and still end up dragging them all the way down the hills. Exhaust brake nothing to get hot and service brakes are ready at the drop of a hat and never have to worry about brake fade or failure.

[dripley]

You just cant beat an exhaust brake. But they are pricey. But if you dont tow the expense might not be justified.

[Mopar1973Man]

Oh the expense is very justified...

 

I bought mine back in 2003 for $800 form Dodge Dealer in Lewiston, ID and not having brake issues... Priceless. The fact I've only install 3 sets of brakes in 417k miles and only one set of rotors. That is also priceless. Even at today's prices for a PacBrake PRXB is $1,200 at least I would buy one tomorrow to replace my current one if it failed. That exhaust brake is even stronger than my current Jacobs Exhaust Brake.

 

This would be my next exhaust brake. Inline I could then have any turbo I wanted...

https://www.dieselautopower.com/pacbrake-c44064-inline-mount-prxb-exhaust-brake

 

Direct mount is like what I've got now that limits me to the current turbo.

https://www.dieselautopower.com/pacbrake-c44075-direct-mount-prxb-max-flow-exhaust-brake

 

 

[dripley]

I did like mine very much towing or not. Stayed on almost all time. But the actuator failed. Its a Banks and they dont seem interested in helping with that. So I would have to drop another grand and that aint in the cards right now. But if I could find an actuator that I could adapt that might be option. I do miss having it towing or not.

 

Plus I would like to spring for a quad, turbo and injectors. The list is endless.

Edited July 29, 2020 by dripley

[Tractorman]

I like the idea of an in-line PRXB exhaust brake, but I wonder any performance is lost being further from the engine.  Anybody know? 

 

I also have logged over 400,000 miles with the my vacuum operated direct mount PACbrake - 69,000 miles on my previous '99 truck, plus 343,000 miles on my current truck.  It has been an excellent unit.

 

- John

 

[Mopar1973Man]

9 hours ago, Tractorman said:

I like the idea of an in-line PRXB exhaust brake, but I wonder any performance is lost being further from the engine.  Anybody know?

ZERO or near ZERO loss. When your under power the valve is OPEN. If there was any loss in performance I would not of high marked 14.7 MPG towing my RV. 

Edited July 29, 2020 by Mopar1973Man

[jtrakel]

13 hours ago, dripley said:

You just cant beat an exhaust brake. But they are pricey. But if you dont tow the expense might not be justified.

 

This is where I’m at right now, regardless of wanting/needing one I have an issue with the brakes dragging which must be fixed first. I believe it’s a bad caliper at this stage, I’m going to tear it down this weekend and the local parts store has one in stock as well if needed. 
 

My last two 6.7’s had the factory exhaust brake and I loved it, my most recent 6.7 I put a inline BD Diesel EB in after the stock turd blower failed and I upgraded. The in-line was a pain at the time as I could not get it to seal up completely which messed with the back pressure. In the future I will address the desire for an EB and will 100% go PACbrake this time around. 

Edited July 29, 2020 by jtrakel

[Tractorman]

1 hour ago, Mopar1973Man said:

ZERO or near ZERO loss. When your under power the valve is OPEN. If there was any loss in performance I would not of high marked 14.7 MPG towing my RV. 

 

Thanks for the response, however I don't think I was clear about my question.  What I meant was,  is there any loss of braking performance with the exhaust brake being mounted farther from the engine?

 

- John

[Mopar1973Man]

Slightly slow to engage being the pipe has to fill with pressure.

[Mopar1973Man]

 

That's about it the closer the exhaust brake valve is to the engine the better the performance. It just that the engine has to fill more pipe area with pressure before hold back occurs. Just that the valve is a distance from the manifold and there is added volume space hence the delay but the hold back should be the same being it will hold up to 60 PSI of drive pressure from the engine. 

[CUMMINSDIESELPWR]

my truck came with a EX brake, was a farm truck towing things. being second owner i dont tow but i still love the ex brake!

 

pros'

i can brake to a crawl without touching the service brakes if they fail (which has happened recently)

 

i can sit back and slap cruise on and ex brake on and let the truck modulate speed on downhills loaded or unloaded. this ensures i have brakes when needed

 

in winter time on snow in 4wd the ex brake doesnt lock tires up but lets them spin and i still have steering but braking as well, saved my arse many times in colorado. (mine being rwd abs only)

 

the ex brake sounds cool.

 

 

 

 

cons...

 

ill get back to you on this when i find one.

[Mopar1973Man]

Bingo... All the exactly correct answers. All pros. 

 

Then con's only con I found is don't be dumb and come down a slick slope with only 2nd drive it will lock the rear tires and start it sliding uncontrolled. 

 

Pros....

 

You can combo with my high idle kit and apply the exhaust brake for super fast warm up. Do take note doing this adds more carbon ot the oil But it possible to warm up from -20*F to full 170*F coolant in under 10 minutes. 

 

If you want real rumble like a big truck...