Brake Pedal Creep
Table of Contents
Brake Pedal Creep
Brake Pedal Creep – Should You Be Worried?
Every now and again at Pellon Tyre and Autocentre here in Halifax, we come across a car problem that sounds frightening to the customer but isn’t always as serious as it first appears.
Brake pedal creep is a good example.
A customer notices that while sitting with their foot firmly on the brake pedal, the pedal appears to slowly move further towards the floor.
Of course, anything unusual involving your brakes is going to worry you — and rightly so. Brakes are probably the most important safety system fitted to any vehicle.
This particular story started not in Halifax, but over on the Yorkshire coast in Bridlington.
A Cold Day in Bridlington
Our customer Joan and her husband had decided to have a day out at the seaside.
Anyone who knows Bridlington will know that a nice Yorkshire coastal day can change very quickly! Unfortunately, the weather turned cold and wet, so Joan decided to sit in the car, enjoy some fish and chips and leave the engine running to keep warm.
While sitting there she happened to keep her foot resting on the brake pedal.
After a while she noticed something strange.
The brake pedal was slowly sinking down.
Naturally, this frightened her. You don’t need to know much about cars to know that a brake pedal heading towards the floor doesn’t sound particularly good!
Later, when the engine was switched off, the pedal became firm again.
Joan remembered that we had carried out some brake work on the car a couple of months earlier, so when she returned home she contacted us here at Pellon.
We booked the Vauxhall in and decided to check everything thoroughly.
Never Guess When It Comes to Brakes
Whenever somebody tells us that a brake pedal is sinking, we don’t simply assume that it’s normal.
There are several faults that can cause a soft or sinking brake pedal, some of which can be serious.
We therefore started with the basics and inspected the braking system.
This included checking the brake pads and discs, brake fluid level, brake pipes, flexible hoses, calipers and the system for any signs of fluid leakage.
Everything looked fine.
The pads we’d previously fitted were correctly installed and wearing normally. The brake fluid was at the correct level and there were no obvious leaks.
That was good news, but we still needed to understand why Joan had experienced the sinking pedal.
What Causes Brake Pedal Creep?
Traditionally, a brake pedal that slowly sinks while constant pressure is applied can point towards a problem with the brake master cylinder.
Inside the master cylinder are seals that maintain hydraulic pressure. If those seals become worn or damaged, brake fluid can sometimes bypass them internally.
The driver presses the pedal and, rather than remaining in one position, it gradually travels further down.
That’s something that needs investigating.
However, modern braking systems are considerably more complicated than the systems we worked on when I first entered the motor trade.
ABS, electronic brake-force distribution, brake assistance systems, stability control and increasingly sophisticated brake servos have changed the way a brake pedal can feel.
So a little pedal movement doesn’t automatically mean that the master cylinder has failed.
Brake Servos Can Change Pedal Feel
Most modern cars use a brake servo to help the driver apply the brakes.
Without assistance, stopping a heavy modern car would require considerably more pressure from your leg.
The servo multiplies the force you apply to the pedal.
Some vehicles use powerful twin-diaphragm servos, giving greater assistance without requiring the driver to push exceptionally hard on the pedal.
This is particularly useful on larger and heavier vehicles.
However, that additional assistance can sometimes contribute to a small amount of pedal movement while constant pressure is being applied with the engine running.
Switch the engine off and the assistance disappears after the stored vacuum has been used. The pedal then feels much harder.
That’s very similar to what Joan had noticed while sitting in Bridlington.
Modern Cars Need Powerful Brakes
Cars have changed enormously over the years.
Many are now larger and considerably heavier than equivalent models from decades ago. Hybrid and electric vehicles can be particularly heavy because of their battery packs.
Manufacturers have therefore developed braking systems capable of safely controlling all this extra weight.
Modern vehicles can have larger discs, more powerful calipers, sophisticated ABS systems, electronic stability control and emergency braking assistance.
Hybrid and electric cars add another technology into the mix: regenerative braking, where the electric motor helps slow the vehicle while recovering energy for the battery.
All these developments have made cars safer, but they’ve also made diagnosing braking complaints more complicated.
That’s why I don’t like guessing when somebody comes into Pellon complaining about unusual brake behaviour.
Test it properly.
Putting Joan’s Vauxhall on Our Brake Tester
After inspecting the braking system, we carried out a road test.
We then put Joan’s Vauxhall onto our MOT brake tester at the Halifax garage.
This equipment allows us to measure the braking force produced at the wheels and compare the performance across the axle.
The results were excellent.
The brakes produced the correct stopping force, and everything indicated that the braking system was operating correctly.
Most importantly, Joan could leave knowing that we’d actually tested the brakes, rather than simply telling her that everything was probably alright.
That’s an important difference.
When Should You Worry About a Sinking Brake Pedal?
Although brake pedal creep can sometimes be a characteristic of the braking system, never automatically assume that’s the case.
If your brake pedal suddenly feels different, becomes unusually soft, travels much further than normal or continues towards the floor, have the car checked.
The same applies if you notice a brake warning light, reduced braking performance, pulling under braking or signs of brake fluid loss.
There are plenty of things on a car that can wait until tomorrow.
Brakes aren’t one of them.
Brake Technology Has Changed
Having worked in the tyre and garage trade for many years, I’ve seen braking systems develop enormously.
Older braking systems were comparatively straightforward. Today’s cars can combine conventional hydraulic brakes with ABS, traction control, stability systems, automatic emergency braking and electronic parking brakes.
The latest hybrid and electric cars can combine conventional friction brakes with regenerative braking as well.
All this technology is designed to keep us safer, but it also means that diagnosing a brake complaint increasingly requires proper equipment and experience.
The driver’s description remains important too.
Something as simple as Joan telling us when the pedal moved, what the engine was doing and what happened when she switched the engine off gave us valuable clues.
Halifax Hills Are No Place for Poor Brakes
Here in Halifax and Calderdale, brakes certainly earn their keep.
We don’t exactly live in the flattest part of Britain!
Drive around places such as Pellon, Queensbury, Sowerby Bridge or the surrounding Calder Valley and you’re constantly climbing and descending hills.
That makes keeping your braking system in good condition particularly important.
At Pellon Tyre and Autocentre we’ve always believed in a simple principle:
We don’t replace parts unless they need replacing.
If there’s a fault, we’ll find it and explain it. If everything tests correctly, we’ll tell you that as well.
That’s exactly what happened with Joan’s Vauxhall.
Joan Went Away Reassured
Once we’d completed the inspection and brake performance test, we could reassure Joan that her braking system was working correctly.
What she’d experienced sitting in Bridlington was understandably worrying, but thankfully it wasn’t the catastrophic brake failure she’d feared.
And that’s really the message behind this story.
If something feels different with your brakes, don’t ignore it — but don’t panic either.
Get the vehicle properly checked.
Sometimes there will be a fault requiring repair. Other times, as with Joan’s Vauxhall, proper testing can confirm that the braking system is doing exactly what it should.
Either way, you’ll know.
And when it comes to brakes, peace of mind is worth having.
