I have a 2002 S60 2.4. The brake seems to be a little soft when first stepped on but becomes harder when it fully engages. Is this characteristic of S60s? The brake just doesn't have a linear feel to it and not very sensitive when applied lightly. Sometimes when stopped at red light the brake pedal would sink by itself (about 1 inch or so) for no reason, is this also normal? I suspect the brake fluid needs to replaced and bled for air but not too sure. Can someone provide some insight for me? Thanks

 

Might want to check you booster.

 

Thks Zigzag. Will ask the dealer check out the booster out during next maintenance.

I bought my S60 used so there is no way for me to know/compare how the brake should feel like when the car was new. Just that the brake on my other Japanese car was a lot more responsive and that's why I'm having this doubt. Are these symptoms common on S60s?

 

Hi raygu.

Brake servo units are extremely expensive, so would recommend completely replacing the brake fluid first as this is the most likely suspect on a 3 year old car.

Manufacturers recommend changing the fluid every 2 years, since it is hygroscopic (absorbs moisture from the atmosphere) which affects its anti-compression qualities (soft, mushy pedal feel) and can lead to brake fade under heavy/prolonged braking when the heat generated by braking friction causes the moisture in the fluid to literally boil.

New brake fluid is almost clear (slight yellow tinge), older fluid is darker (brownish). Only use new fluid from a fresh, unopened container. Preferably the container should have stood still for 24 hours - if it has just been shaken around in the trunk of your car on the way back from the auto spares shop, it could have small air bubbles in it. A quart bottle should be more than enough for the job.

In UK minimum quality standard for brake fluid is DOT4 but since DOT5.1 only costs a few pennies more, I changed the fluid in my 2002 T4 to DOT5.1 within a couple of weeks of buying it earlier this autumn.

If pedal is still soft after carefully changing the fluid, then you'll need to get the servo tested.

Hope it's only the fluid!

BB

 

Thank you BB for your thorough explanations. Actually this is exactly what I suspect in the first place. I wasn't sure about this just because the symptoms are still very light--my wife probably won't even notice this when driving. I will arrange the dealer to have the brake fluid changed. You're right, I'm living in HK and during spring time, you can literally squeeze water out of air.

 

You are welcome.

Wouldn't it be nice if you could squeeze beer out of the air instead?!

BB

 

Finally got the brake fluid replaced before X'mas. The difference was quiet noticeable. The brake feels strong and solid again, just the way I like it!

 

Fantastic, glad it's solved.

Much cheaper than a new servo!

BB
[sm=Awwww.gif]

 

The soft braking just now happened after I had to make a very sharp turn brake. The brake pedal if ok for like the 1st inch then softens where I feel like I need to push to the floor. Thought I heard a crunch at the very bottom. Ugh?
.

 

That is the sensation of bursting something in the braking system. You may have a puddle of bake fluid somewhere and low fluid in the reservoir.

 

Thanks. No puddles found. Maybe maybe a new smell, not sure tho. Will ck the res for levels. At the same time, but no now, the ck brake light message came on. My brake light is buggy in that it works until the car gets "unsettled" (ie: dead battery jumped, or service). What else to ck?

 

I suppose it would not be too unusual to have ABS kick on and dump some fluid out in this maneuver you mentioned. So I guess it would be good to clear up whether this happened once or if it happened every time you used the brakes after that first time.

If you're losing fluid, then those concerns will be greatly simplified (i.e. stop the fluid from coming out wherever it's coming out).

 

If the reservoir is maintaining the same level, there is no leak or dumping of fluid.


A drop here and there, from a possible drip of the filling process is not to worry.

 

Update: dealer replaced brake modulator. $$$ certified used part brought the price installed down to 1300 from 3400!