XR5 MB - Brake pedal behaviour - feedback pls

[allanv6gt]

For some time I have had concerns about the state of the brake master cylinder.

The pedal does not hold booster/fluid pressure and bleeds down to a certain point - about 50 mm above floor with a hard mechanical sound knock at bottom of travel (like a bump stop). First occured about 18months ago @ 30000kms, and has been slowly getting worse (now 49000kms).

The brake fluid has been changed three times now - once by my usual mechanic Jan12, and twice by dealer in the last month (they're trying to be helpful !!). I'm not losing fliuid but it just don't feel right.

With so few XR5's here in CBR passing thru the dealer the task of making a comparison is almost a no-goer.

Could other XR5 owners pls provide some feedback on pedal behaviour after conducting the test below.

1. Start the car and let idle.
2. When stationary, put your foot on the brake and hold it there.
3. Apply further foot pressure without lifting up.
4. Apply more foot pressure until the pedal bottoms out (or not)

Does yours maintain that initial pedal pressure?
On mine, the initial pressure is ok, with any further foot pressure resulting in bleed down of boost/fluid until a hard travel stop is encountered. If you jump on the brakes it stops fine.

A comparison I did last week with a used XR5 in the dealers yard had that XR5 maintaining boost pressure on the pedal (still a bit spongy as expected for on-boost) and did not bottom out like mine does.

Any feedback most welcome.
I'm happy to chat face-to-face with any other CBR XR5 owners - PM me offline.

[allanv6gt]

I'm still very interested to hear from anyone with an XR5.
Comparison with other peoples cars is one way of convincing the dealer that a problem exist with my car.

Also, I spoke to a local brakes specialist this morning.
He suggested the problem was an internal seal somewhere allowing fluid bypass, but without fluid loss from the system.
To solve the problem, he suggested start with the master cylinder, then check ABS etc.
Failing a satisfactory dealer response, next step would be Fords Customer Service Centre.

[ope126]

Originally Posted by allanv6gt

I'm still very interested to hear from anyone with an XR5.
Comparison with other peoples cars is one way of convincing the dealer that a problem exist with my car.

Also, I spoke to a local brakes specialist this morning.
He suggested the problem was an internal seal somewhere allowing fluid bypass, but without fluid loss from the system.
To solve the problem, he suggested start with the master cylinder, then check ABS etc.
Failing a satisfactory dealer response, next step would be Fords Customer Service Centre.

Are you only interested in XR5 Turbo's because they are manual?
I.e Clutch / Brake fluid slave cylinder.

Can any one else help?

[allanv6gt]

I'm led to believe the master cylinder in the XR5T is different to other models, and the shared fluid resevoir arrangement might be the key difference (don't have access to master cylinder part numbers across the models).
XR5 has ABS and EBD etc etc, don't know about other models.

Dealer service mgr is trying to check against other XR5s coming thru workshop and used car yard...but they see so few here in CBR.

Happy to receive comments from other models though...... Shouldn't make any difference manual/auto.

And I'd really really like to press the pedal in person on other XR5s here in CBR. Don't need to drive anywhere, just sit in level driveway on idle and press the pedal with no handbrake or hill-hold active. I know the simple test I need to do, just a bit hard to describe. The used XR5 I tried @ the dealers felt very different on the pedal - but that is only 1 example.

[DRU842]

Not experiencing the problems you describe; pedal is solid & progressive.

[allanv6gt]

DRU842 -thankyou so much for the feedback.
I have another session (no. 4) with the dealer tomorrow for "further diagnostics" as suggested by Ford Customer Care.

[allanv6gt]

Session 4 - only feedback was "consistent for model". No details as to what was actually checked, unlike some other job sheets I was shown.

They say "others sag as well" (my paraphrasing)
I say " not the two examoples I've personally tried, nor DRU842 above.

Now have their Ford OZ Service Operations Consultant (aka manufacturers roving tech specialist) booked in for 9 May.

You just lose confidence in a car when your brake pedal sags under light pedal pressure when merely sitting at the traffic lights.

Still happy to receive comments from other XR5 owners.

To be continued......

[DEVO'S MB XR5T]

Just sitting here trying it for you now.
I put my foot on at first time till it stops, lines up with accelerator peddle, when I go to push further maybe goes 10mm past accelerator peddle but no where near bottoming out like yours.

When you say CBR where is that? Canberra?

[allanv6gt]

Devo - thanks.

Mine sags down to a 'hard' stop and mechanincal knock sound i.e. no boost left but no to floor. Ddefinitely no on-boost slight sponiginess remaining. No the floor, buit then I don't know what the maximum piston travel is.
I'll need to check again that it hasn't hit an internal bump stop somewhere.
....But certainly more than 10mm, more like 30-40mm extra travel.

Very disconcerting.

p.s I read on another thread someone took 16 visits to get a problem fixed. Well, 4 down and only 12 to go. Yippeee...not !!

[sleek7]

Will give mine ago later this evening if you are still interested Allan. What city are you in btw?

[allanv6gt]

CBR = Canberra.....just like your airline luggage tag.

Session 5 - Master cylinder was replaced yesterday (Friday)...no difference.
I'm feeling some resistance but it just doesn't hold pressure after initial application of brakes. And any very slight re-pump of pedal just bleeds down lower until that 'hard' stop and knock.

With the Ford Oz roving tech in attendance, I tried the brake pedal on a new Territory on the basis that the tech told me the new brakes 'lose' pedal feel just after you use them. Well, all I felt was the return spring pressure. Zero 'brakes'. Very unnerving.

The Ford OZ tech et al spent a good half hour look for fluid leaks under the car, but I haven't noticed any meaningful drop in resevoir level. I did however notice slight moisture on the pedal piston covers of the original master cylinder inside the car under the dash - first signs of (external) failure AFAIK.

As an aside, I bought a 2007 Fiesta last weekend (from the same design era as the Mondeo).
It has ABS and the pedal don't bleed down.......remains slightly spongy (on boost) as expected.

[mik]

sounds pretty weird Allan, er sorry i have no experience with these cars, just throwing a thought or two out there old mate, by all means shoot me down , on some cars there is an adjustment between the foot pedal rod and the master cylinder to get the pedal /stroke at the right height, just wondering if ......A. it has one of these and B. if it has a locking nut that could have come loose and allowed it self to wind down giving a false impression faulty brakes, the other thing i was thinking is how much meat have you got on pads? also another thing , is it possible a brake hose is faulty blowing up like a balloon?
best of luck with it .

[tudorsedan1930]

I have a 2014 Territory Diesel . I have had it from new. My son drove it recently an said what’s wrong with your brakes? I said nothing.
He has a habit of pushing very hard on the brake pedal when starting a car and found that the pedal pedal on the Territory slowly went down to the floor. I had not noticed this as I start with the hand rake on and only apply enough pressure to brake efficiency when driving . I have since tried excessive pressure on the brake pedal while stationary at the lights and the pedal does creep down. A pump will bring the pedal firmness back but excessive pressure will start the pedal moving downtown to the floor. There is no fluid loss and the car brakes well. I have asked different brake shops and they have no idea of the symptoms. I suspect this symptom was there from new and was not recognised till now. I too would like to know a fix.