Problem is back. 👎. The longer I drive and have to use the brakes, the worse it gets.
I’m beyond frustrated. As a mechanic for most of my adult life, I am perplexed.
I can’t believe no one else is having or have had an issue like mine.

I have no idea how the ABS systems work on the modern brakes, but when they first started using them they would release the brakes a bit to prevent a wheel lock up. Now that they have added a computer, and the system is tied to all 4 wheels, its not out of the realm of possibilities they have adapted the the brake system to apply more braking to wheels that the system has determined has more traction and can use more braking. If that is the case, as that system gets older, its possible the mechanical part of the system isn't functioning as well as it did when it was new. The older systems were just bypassed when they no longer functioned the way they were designed to. Can't really do that with the modern system without a major rework.

It would be interesting to hear from the experts how the modern ABS systems work and see if that system could be your problem. Then suggest ideas on where to begin to address the issue. If it is indeed an aging problem with the system, its going to become a bigger issue as this stuff gets older.

Its also likely many others have experienced the same issue you are having, but have been unable to cure the problem and have given up and are just using the truck knowing the problem is there. Some people probably have no idea dragging brakes are not normal. I believe many of the trucks of this era are no longer in good enough condition that many of the owners don't want to invest the money into new parts that isn't solving the problem. They have thrown enough money at it that has not fixed it, they are just going to deal with it the best they can.

It's really uncommon but I've run into a couple instances where the booster was failing and slightly engaging the brakes.

Start by cracking a bleeder to see if there's hydraulic pressure causing the drag. If so, it could be the booster. When the brakes drag again, loosen the master nuts a couple turns and see if the drag goes away. Note, the pedal will have extra travel so be careful.

Did you get rid of the calipers with the phenolic pistons yet? The failure mode you're describing is exactly what happens with the phenolic caliper pistons.

Both calipers have steel pistons and are free. If I open the bleeder, I can easily collapse the caliper pistons.
New hoses and pads.
If the booster was bad, all 4 brakes would drag or lock up.
I loosened the Master from booster and no difference in the drag
What's left? ABS?? What If I remove the ABS fuse? What would happen??
Is it possible that the brake pads can expand when hot? I've never heard of this, but at this point, I'd suspect anything.
Everything that I've researched on the internet, I have checked or replaced.
Buy the way, My truck just turned 35K miles. It is not beaten and kept clean and maintained like all my other vehicles. The truck is a 12 year old new truck. This issue started several years back and has progressively gotten worse. The longer I drive it the more likely the front brakes start to drag. Yesterday after a drive in stop and go traffic for about an hour, the front brakes were steaming hot and smelling. Today, I went out and the front brakes had no drag at all. Seems heat related to me!!!

could it be possible the calipers are binding on the slides or pins when heating up ?
know you have said opening the bleeders releases the offending caliper[s], but could they be cocking on the mounts slightly during application, then not releasing fully, building up heat, then getting worse every brake application ?
just throwing something out there, trying to help.
i have been told i'm full'a $heet before, so this may be another of these times............

No you aren’t full of it😂😂. And no the calipers aren’t cocked or binding. Thanks for the suggestion though

Seems like this should be easy to diagnose. When they are acting up jack a wheel off the ground and open the bleeder. If it frees up then its a hydraulic issue. If it still drags after opening the bleeder its a mechanical issue. This needs to be done to continue diagnostics.

Just did this this morning. Cracked the bleeders and fluid dripped out. No pressure. The calipers were both loose. Last night I couldn’t turn the tires because they were so tight. Over night, no drag at all.

You have to do this when the brakes are dragging. Even waiting 15 minutes gives you false information. The problem can go away that fast. If its a reoccurring heat issue, you have to open the bleeder screw while its hot and still dragging to see if there is still pressure there.

Get them hot and dragging, pull into the unoccupied end of a parking lot, stop and open a bleeder screw (caution, the fluid will be hot). If it squirts out and the wheel turns, there was still pressure applied.

You need to do this when its hot and acting up. Not sitting over night. No wonder you cant figure it out.

Tell me how you really feel. How about some good in put as to what is going on. It’s easy to sit in the bleachers and criticize.
I’ve given up to date info as to what I’m experiencing. Criticizing isn’t helping.

Well with your attitude I wont waste my time trying to help you. After all you do claim to be a mechanic so you should not need my help.

68LAR, Just for your information, NITROUSN is a service manager (or in some other position related with dealership tech service) at a Chrysler dealership. The simple fact that he spends his time assisting us here is extremely helpful. He deals with Chrysler techs every day, short blunt answers is what he has to do on a daily basis, he doesn't have time to exchange pleasantries. If you want answers, he has a pretty high success rate here.

At least the calipers on your RAM are on sealed lubricated slide pins. The front brakes on my 2001 Dakota are in a word, chit. The calipers "slide" on a cast rail on the caliper mount bracket. Through years of Wisconsin salty winter highways the calipers wear "notches" on the rails and after time the calipers never fully retract. Rubbing increases, calipers get warm/hot, slide rail builds up crap and wears and gets hot as well. At one time I took a 4" grinder to the slide rails and ground them down to get rid of the notches. But that leads to too much play in the area where the slide rails retain the calipers. Just a cheap crappy design, lousy brake feel, brakes dragging on when trying to stop on slippery surfaces. When I put this Dak chassis under my 56 Dodge build I'm replacing the entire front brakes with the setup for a 2003 Durango, which uses slide pins. Much better braking, much less caliper drag, much better braking feel.

On ABS systems, the braked wheel has to slip about 10% to 20% less than the actual vehicle speed before the ABS does anything. Two things required, the wheel has to have the brake applied, and the braked wheel has to turning slightly slower than the actual vehicle speed. If not both, the ABS does nothng. If the brake on that wheel circuit is not applied by in cab brake pedal pressure, and if the wheel is not slightly sliding already, ABS just monitors the wheel speed. Active vehicle stability is different. If the stability system senses a vehicle yaw thresehold out of the intended track, of if the traction control system senses a driven wheel spining faster than the actual vehicle speed, then the ABS/Stability control can actually apply brake pressure to that sensed wheel independent of the driver input on the brake pedal. The system may also reduce engine power independent of the driver input to get that wheel speed to match the actual vehicle speed. So its not likely the ABS/Stability system is applying a brake independent of the driver input to cause brake drag. Even if a wheel speed sensor was well out of adjustment, the ABS/Stability system would not function and recard a fault, possibly shut down and turn on the ABS light.