Hyper sensitive brakes on 04.5 Ram 2500 quad cab long bed

Searched on "hyper sensitive brakes" but maybe I'm not doing it right. Just drove 7 miles to store and back no problems but as traffic slowed to red light to my street on way home I rolled to - not quite a stop so lightly touched the brakes and they screeched to a halt. I let off the pedal and truck operated fine moving forward, put 4 way flashers on down my street until I found a gravel parking area to pull off and was just rolling and touched the brakes and front left wheel locked up stopping the truck. was not completely on the gravel, just right front and it dragged the wheel. quarter mile down the road I pulled into my driveway downshifting to slow then tapped pedal and screeched to halt. Mileage 220k, I bought truck at 170k and have replaced rotors, calipers, pads front and back in last 5k miles. Don't know if any other brake components have been replaced like master cylinder. No ABS or other brake warning light on while driving. Any ideas?

 

Did it smell like the brake was hanging up at all? Almost a burning electrical smell?

 

There are so MANY factors or parts that could be playing into this, but it seems as if at least one of your calipers is dragging the rotor somewhat at least partially without fully releasing.

The first piece of advice that I would give you is to use an IR/laser thermometer (if you odnt have one you can get it affordably from amazon or Harbor Freight) and then use it to check and compare the temperatures at the brake pads, rotor and wheel bearings of all four wheels after you drive to the store again.

Any high temperature variation past about 7*F will tell you which wheel caliper or bearing is acting up.

Report back here what you find and Im sure lots of members will try to help out with a more specific diagnosis.

 

Good advice be @seafish . You can do the same test by using your hand - just reach into the rotor area very slowly in case a rotor or hub is extremely hot. I would pull of the roadway about every two miles (if it is safe to do so) and check the rotors for excessive or uneven temperature. If a brake pad is dragging, the heat will build quickly. Also, the more frequently you check them, the easier it will be to determine if you have a rotor or a bearing overheating.

- John

 

I'm not smelling that telltale overheating brake smell that I’ve experienced many times with my’98 Ford diesel van. It’s notorious for that and I need to replace the flex lines on the front brakes. I will get that infrared temp sensor tho just to make sure the Dodge isn’t dragging pads.

 

I did feel the wheels with my hands for temps and they were warmer fronts than back wheels to be expected. Not too hot to hold my hand on for a while (6 spoke factory 17” aluminum rims). Will get infra red temp sensor tho to verify.

 

I’m wondering if the front brake flex lines are the problem not letting brake fluid back flow after applying brakes being 19 years old. The replacement maintenance never ends - new $750 ball joints, rotors, pads, calipers all around 5k miles ago, hvac heat and a/c core replaced, new blend door USA blend doors, 4 tires, rebuilt 6 speed, transfer case, clutch pressure plate, t/o bearing etc. never ends

 

I know how you feel, I've owned my 03 since 2019. I'm still doing catchup work roughly 5 years later. Hopefully your brake issue is something small, im interested to see what the cause is; my calipers and lines are OEM at 250K+.

 

@VFabricius, The front flex hoses may be collapsing and causing your issue. I'd replace and do a brake fluid flush if not already been done. Old fluid in the system can cause calipers to hang/seize up due to the water contamination in the fluid over the years. Fought that battle on my '01 1500. Flushed and replaced flex lines, all better!

 

While the rubber brake lines do obviously age and deteriorate on the outside, is not so much that the soft brake lines collapse due to age, rather that the steel clamps that holds them to the frame begin to corrode and rust and as they rust the clamp expands and in size and digs into the hose ...slowly reducing its core diameter and not allowing brake line pressure to release properly. Of course you should do a thorough inspection of ALL the brake components, and if you can SEE the brake hose clamps rusting, that is very likely at least part of the cause of your problem.

Just my .02

 

Happened to a buddy a few weeks ago. New hose and all was well. Misdiagnosed asa caliper at first. Rust jacked hose was the culprit.

 

I eliminated it being a caliper/pad overheating and making brakes sensitive. I drove truck down my subdivision street in AM cold and barely rolling down slight grade applied the brakes and they immediately locked and the anti lock kicked in. Gonna replace flex lines and flush lines. Will report results in a couple days.

 

It's not the lines, look somewhere else.*
Hydroboost would be my closest idea without having hands on.
Or the pads... which would be fairly cheap to rule out.

*Lines do not raise pressure, the can keep pressure but never raise.
You have apparently to steep of a pressure raise in your system.

 

Ozy...respect your response and tend to agree somewhat, something is raising the brake line pressure but how would the Hydroboost raise it? If it failed, I would think I would have a hard pedal and no power steering which I've encountered on my '99 and replaced the HB on it. Can the HB fail the other way and raise pressure? I'm a believer and trying to solve this here because all stealerships do is throw my $$$$ at it and "eff" you if it doesn't solve it, we'll try something else. But this may be beyond my capability. Since the truck is 20 yrs old and replacement flex brake lines wouldn't hurt to replace and really a maintenance items, I'm going after that now and will report results here.

 

There is a control valve inside the hydroboost unit that is actuated by the brake pedal pushrod. This control valve uses power steering fluid stored in the accumulator to multiply braking force. It is possible that this valve may have developed a hair trigger.

Can you test brake operation in a graveled area? This would give a better idea as to which brakes or if all brakes are being affected.

- John

 

Theoretically if it was the hydro boost wouldn't it apply all brakes evenly? I cant see how the hydro boost would cause only the front left to lock up and not effect the other 3 brakes.

I might have read the initial post wrong but sounds like the front left is the issue not all 4 corners.

 

I think you read the initial post correctly, but I think his description of the events may need more detail for clarification.

First Event:

Note the use of "they" (indicates more than one wheel).

Second Event:

Not sure which wheel is dragged. Did the left front lock up and the right wheel drag in the gravel? The OP was probably under a bit of stress at the time and it may have been difficult dealing with traffic and observing the braking issue simultaneously.

Hopefully, @VFabricius will confirm that only one specific wheel is locking up, or if something else is going on.

- John

 

I still think it is a problem with pad/disc match.

Is it confirmed that there is all in perfect shape?
He might have lost/separated a pad and and all is left is the steel base of the pad, bitting into the disc.

 

Here's a great tool for the tool box to help with brake issues, i.e. rotor run out. https://www.harborfreight.com/clamping-dial-indicator-63656.html?_br_psugg_q=run+out
The price point wont bust a budget but sure will help finding a warped rotor! Been a great help with checking rotors when rotating tires to make sure things are good to go!.

 

When I was young and foolish I owned vehicles where I let the brake pads wear down and fall off. But the result was the telltale horrendous metal on metal grinding noise from the rotor and brake pad plate when I applied pedal. It never locked up the brakes, though.