Need help!! Loss of brakes

[Gonzoa24]

I have been trying to figure this out for awhile and I haven't been able to come up with anything so I'm hoping my Ranger brethren can help!! Whats happening: whenever I do a left hand U-turn, or even a sharp left turn, after straightening out, my brake pedal sinks down to the floor and I have a loss of brakes until I pump em back up and they pressurize. Ive been thinking vacuum leak but haven't been able to find one yet. any ideas? I would really appreciate some input. Shes and 02 ranger, 4.0, 5 speed, xlt...her name is Molly! thanks in advance for any and all help!!

 

[RonD]

Welcome to TRS

That's an odd one.

I assume the brake fluid in master is full, I know obvious, but have to ask?

My first thought would be one of the Flex hoses on the front brake calipers is leaking.
When you turn the wheels left or right it is leaking so you lose pressure and when wheels straighten out it holds pressure.
Check each hose for fluid leaking on the outside of the hose.

You would be losing brake fluid in the master if this was the case, are you?

Losing vacuum in the power booster only effects how hard you have to push on the brake pedal to stop, you don't lose the brakes just gets very hard to push down on the pedal.
And pumping the pedal wouldn't restore vacuum, you loose vacuum each time pedal is pushed.

 

[Gonzoa24]

The master is full and I haven't seen any leaks. I had to edit the first post by the way, it only happens on left hand turns...just adding to the "strangeness." The pedal doesn't really get hard to push, it just sinks all the way down.

 

[adsm08]

Check your wheel bearings. If one is loose and letting the wheel wobble it can compress the caliper causing your symptom.

 

[aspevacek]

I think it is something to do with the RABS. I get the symptom every so often doing a turn in reverse. It does not happen often it has done it for several years. I have not ever been able to find a cause for it, just one of those things I have learned to live with.....

 

[Gonzoa24]

Well yea I've been dealing with it since I got the truck three years ago but I would like to eventually fix the issue

 

[adsm08]

I think it is something to do with the RABS. I get the symptom every so often doing a turn in reverse. It does not happen often it has done it for several years. I have not ever been able to find a cause for it, just one of those things I have learned to live with.....

We should look into that.

 

[aspevacek]

We should look into that.

My issue is completely random and near impossible to replicate. It has done it with 2 separate sets of stainless steel lines on the truck. I had the Sky Jacker lines on and in 2010 when I swapped from Sky Jacker to JD. I put on the included Earls lines from JD. The Master cylinder would be suspect with the pedal dropping to the floor but again it is a once in a while thing, a master cylinder would progressively get worse as it aged and had internal leakage. I have had the rear drums off many times looking for possibility of rear wheel cylinder leakage, never found any have rebuilt the cylinders a few times over the years as well and threw new ones on the last time I did the brakes.

I Know you stay right around the way from me, I actually bought a home down town Mechanicsburg. Let me know if you ever need help with any of your projects, and we can line up time off together. I am very capable at working on vehicles.

 

[AllanD]

a Pedal that gets sucked to the floor is a problem... with the POWER BOOSTER.


I had that problem years ago with my '69 Mustang.

And a distinct hiss like an angry snake under the dash