Weird brake issue!

[SofaKing95]

Hi, all! In all my years of driving, Fords and Mopars from MY 67-99, this has never happened, I come to a stop, then it feels like the brakes let loose and it rolls forward about 3 feet! Had the brakes all done in '21. Haven't put more than say 4000 miles on them. But mostly city driving. I have a mechanic to look at it but anyone here had that problem? When the brakes were done they mentioned they had to lube one caliper and keep it from sticking. Would a stuck caliper cause this? I get no noise, pulling, or pulsating on the brakes. Weird and makes me nervous!

Did it just start happening or has it been an ongoing issue?
ABS isn't kicking on, correct?
My first reaction is the master cylinder -- maybe check brake fluid level and look for "wetness" (i.e. leaking) around master cylinder body.

 

[C420sailor]

The whoop and grumble sound description makes it sound like the ABS pump is kicking on

 

[Pete Deering]

Did it just start happening or has it been an ongoing issue?
ABS isn't kicking on, correct?
My first reaction is the master cylinder -- maybe check brake fluid level and look for "wetness" (i.e. leaking) around master cylinder body.

Did you do it have anything done too the brake system?

 

[J_C]

I come to a stop, then it feels like the brakes let loose and it rolls forward about 3 feet!

This is what makes me think it's ABS, that if it were something else, it should affect braking at higher speed, and decelerating with a closed throttle (not giving it gas), vac for the booster should be at its highest. The ABS sensor tone rings moving slow at low RPM, produces the weakest signal.

 

[Pete Deering]

This is what makes me think it's ABS, that if it were something else, it should affect braking at higher speed, and decelerating with a closed throttle (not giving it gas), vac for the booster should be at its highest. The ABS sensor tone rings moving slow at low RPM, produces the weakest signal.

I have same problem. When I go down a slope driveway. It ready show up , I have too put it In neutral and it stops.
It happen after I did my front brakes. I replace both wheel hubs and sensors, rear and sensor, no change.
What I believe, what is causing it, is a restriction in the front brake line. a Tight bend in the line. It all happen after that replacement.

 

[J_C]

^ But shouldn't a restriction in the line due to a tight bend, only decrease the braking force on that one wheel, so it would be a safety issue when braking hard at high speed or on a slippery surface, but not so much going slow with reasonable traction? I don't see how that would cause the vehicle to seem to let off the brakes in this situation, unless there's air in the line(s).

Did the line collapse at the tight bend, does it have a kink on the inside of the bend? Does it seem to bleed normally? If in doubt then I'd just replace the line, rule that out if nothing else.

 

[joney]

Did you do it have anything done too the brake system?

Not yet. Going to ask my nephew if he can check out the brakes. Nobody working yesterday or today, I believe it's deer hunting season also or soon.

 

[Pete Deering]

^ But shouldn't a restriction in the line due to a tight bend, only decrease the braking force on that one wheel, so it would be a safety issue when braking hard at high speed or on a slippery surface, but not so much going slow with reasonable traction? I don't see how that would cause the vehicle to seem to let off the brakes in this situation, unless there's air in the line(s).

Did the line collapse at the tight bend, does it have a kink on the inside of the bend? Does it seem to bleed normally? If in doubt then I'd just replace the line, rule that out if nothing else.

?1. Yes, and has a kink in the steel line.
?2. Yes it bleeds normal
After the hard line replacement. 15+ Years ago. I replaced driver side front brake pads and the problem surface.
I replace both front HUDs with sensors, rear sensor. No change.
I spoke too the company, where purchase the short flex line from.
Its not there line. The only thing left. Is the kink line.