Groaning/creaking sound when releasing brake pedal

If you mean the sound like an old hinge, that is the sound of the bellows on the brake booster and the pivots on the brake pedal as it moves. You might try spraying the brake pivots with a bit of white lithium grease and spray the rod and bellows with some silicone spray.

Is the brake booster right behind the brake pedal in the firewall or where exactly is that located? Also the bellows?

And you are referring to the tie rods correct?

The booster parts to lube will be up under the dash. There will be a pivot point part way up the brake pedal where the actuator rod connects, then another at the top of the pedal. The rod part way up goes into the brake booster bellows.

Well I went ahead and sprayed the joints and pivots with a bunch of lithium grease, sprayed the stuffing out of the rubber rod boot with silicone spray just today. I also forgot to mention that I had the full set of shocks and struts replaced a few months ago, ever since then, the brake pedal sunk in a bit more than usual, I am guessing it is because of the rear struts being replaced and the brake line needing to be disconnected, thus some air entering into it. Also, whenever I drive over bumps while pressing the brake pedal, the pedal will kind of push back at my foot, do you think that is the brake booster or simply air in the brake lines?

I will hear how the brake pedal sounds tomorrow morning since I have not driven the car after lubricating everything, and I will also bleed the brake lines.

So I drove to work this morning and took a few videos of me slowly moving my foot off the brake pedal. This first video is a few minutes out of the driveway when I came to a stop, you can clearly hear the groaning noise coming from the brake pedal area.

In this second video, the groaning noise drastically dropped, this was taken literally only a few minutes after the first video after a couple of stops. Also, lots of creaking coming from the brake pedal whenever I step down on it. It seems as if though after some driving, the groaning noise that is produced from slowly releasing the pedal, goes away.

I think I might just have to replace the brake booster.

The creaking is not from the booster, it sounds like the upper pedal bushing. The sort of hiss that you hear is the valving on the booster as it lets air in to create the assisting force. If it has been driven a while with the various points rubbing it may take removing the brake pedal to get the lube in where it is needed. It is also possible the bushing in the pedal is damaged after fifteen years.

So I would need to replace the bushing in the pedal? Is there a part number for that? And how hard is the job?

It depends on which pedal assembly you actually have. Some the pin can be removed and the pedal arm removed to work on it. Others are welded and not repairable. You should be able to see the pivots if you look at the top of the brake pedal arm. If it has adjustable pedals it will be repairable. Fixed pedals, you have to remove the pedal assembly and replace it. However, Ford does not show parts for either one so you would end up with used parts most likely. I think I would try a bit more lube first.

Sorry for the super late response. I still have this issue with the brake pedal. Really loud groaning noise when slowly releasing, I have the sprayed the metal joints and entire assembly with chain lubricant and also white lithium grease. I found a pedal assembly on eBay but I just wanted to show you the picture to find out what specific parts I need to lubricate. If I did not mention it before, probably five months ago I replaced the front disc, pads and calipers and the rear drum brakes were completely replaced at Firestone a little over a year ago. I have had the issue for over a year now.

I have been reading plenty of forums very similar to my symptoms and a lot of people are saying this is normal, or it could be lack of grease/lubricant on the metal plate behind the brake pads that make contact with the caliper. I put silicone grease on these when I installed my pads not too long ago, but the noise has been present, like I said, for over a year.

If you have someone set in the car, close the door and step on and release the brakes can you hear the noise outside? How about if you set in the car and with the engine off, pump the brakes to use up the vacuum in the booster. Does the sound still occur? If not start the car with your foot on the brake and listen as the vacuum refills the booster, then let the pedal up fast, what do you hear?

The noise only happens when the car is in drive, not park or neutral, and you can hear it from outside but you can also hear it very clearly from the inside as if it is literally coming from below the steering wheel, you can feel the groaning, it is definitely coming from the front of the car.

People in the forums I was reading were having the same issue, that the noise only occurred when the car was in drive, or in motion, and that this was simply the brakes stopping the car from moving so that is why it makes the groaning noise, that it is “normal”. But I have had this car over two years now, this problem started about a year ago.

It sounds like the brake pedal pivot it dry or you have a sub frame that is cracked. Can you get a flashlight and look up under the dash to see if you can tell if something is moving more than it should? It does not make sense that it does not to it in drive or reverse, strange.

It only makes the groaning noise when in drive, not in reverse, that is the weird part.

Ken, that was my first thought, had him lube the pivots, still noisy. However, if you can hear it outside the car and feel it as well I would look at the sub-frame mounts where they bolt to the rest of the chassis. It could be the bushings are shot and the groaning is the sub-frame shifting in relation to the rest of the chassis as the car moves.

Subframe mounts, where are those?

Under the car. There are four bolts that retain the front sub-frame to the chassis. Two in front two toward the rear. The sub-frame holds the engine and transmission in the car. What you are hearing could be those mounts creaking a bit as they are loaded and unloaded by the vehicles motion. When you step on and off the brakes the engine and transmission transfer power through those mounts to move the vehicle. If the bushings are worn and move even a small bit they could creak. There are kits out there to replace them. The two rear ones are the most failure prone and one sets just about directly under the drivers foot well. However, while they are replaceable you might be better off just spraying them with some silicone lube to see if you can quiet them. They are not really difficult to replace but if things are rusty they can become an issue.

Brake calipers.

Thanks for the update. So were the replacements not correct or something else?

It looks like your initial diagnosis was pretty accurate actually. He clearly stated that he replaced the BPA (brake pedal assembly) after which the car developed the problem. There was no doubt about your recommendation concerning lubrication and the actuator rod mechanism to the brake booster: that was exactly where the car's problem was. When the BPA was replaced, the retaining and actuator mechanism as well as the BPA as a whole had to be assembled correctly and lubrication done in specific places. BPA can get stressed (or warped) by bolting forces and can easily create "grabby" braking effects which results in vibration noise that is exaggerated through hollow steering column and other metal parts and the bracket itself to the firewall (very thin metal component part of BPA). colder and humid conditions could result in similar vibrations within external braking parts (rotors, caliper pistons, pins and pads) especially when the car isn't being driven (again "grabby" effects result in vibrations that are echoed through metal parts and through hollow tubes right into the driver's hearing). As far as the loose braking (he puts it differently: "sunk pedal" would be a different issue namely brake fluid dynamics as well as wheel brake parts and not BPA- actuator rod-booster issue. Lastly, he mentions new struts and shocks: again a different issue: incorrect struts installation (which are bolted to the knuckles which hold the braking parts) would also result in different symptoms such as misalignment and other noises. This was a great question because it spoke of a very unique type of noise that may or may not resolve on its own.

Correction: I just realized the BPA was never replaced only the external brake parts and the struts. Nevertheless, the advice you gave in your answers to his question was undoubtedly what his car needed. Removing the BPA and working on the actuator rod (not to mention releasing the retaining mechanism and reinstalling it) can be very intimidating task. There is something mysterious about these parts: the BPA, the Brake Master Cylinder and the Brake Booster just don't seem to "sink in" well with most DIYers.