[Chappers 71]

I was a bit hard on the brakes yesterday and was rewarded with that burnt friction material smell, to be honest for a brief moment I didn't think the car was going to stop but it did. When I next went to use the brakes they were not good, longish pedal car not slowing down but did improve on the way home as they cooled.

Took the car out today & the brakes are much better but still not 100%, brake pedal feels a bit longer than usual.

So I was running red stuff ceramic pads but swapped out the front pads for brembo non ceramics as they needed replacing & whilst running the red stuffs they had ruined 2 front pairs of discs, steering judder under braking.

Two questions, is it likely that a brake fluid change will sort the long pedal & secondly will all ceramic pads ruin non drilled/grooved/dimpled discs as after yesterday's moment I may go back to ceramic pads on the front but I don't want to ruin another pair of front discs.

As a side note the current Z4 30i is a surprisingly quick car & seems able to get the power down very nicely of roundabouts

[nomiS330d]

I had a similar situation a few weeks ago. I am running normal discs and newish brembo pads. I was going at a bit of speed and braked hard to a standstill. After that the peddle went long and the pads had no bite. When I stopped the discs were glazed slightly blue! I went for a drive and the brakes were making a graunching sound and weren’t good for the first couple of slow downs but did come back after a while and felt better than ever! Been fine since.
I wonder if once the fluid has been cooked in your experience it’s ruined and needs replacing? I think I just cooked my pads which have been ok since burning the glazing off?

[rasa bmw]

never had fade with yellow stuff and zimmerman discs,,same when i had red stuff and zimmerman discs.plenty dust from yellows,,but if you want decent stopping then dust will always be more

[mjn77]

No fade with EBC grooved discs and yellow stuff pads.

[Chappers 71]

Am going to change the brake fluid first & I may upgrade the brake hoses at the same time, then see what the pedal feels like.
I suspect the best way to avoid what happened the other day is not to let myself be provoked into driving like a c*nt

[Chappers 71]

Have just ordered a full set of stainless steel braded brake hoses, my man maths dictated that as I am going to change the brake fluid it makes sense to swap out the hoses at the same time as mine are all the originals & are 14 years old & have 120,000 miles of use

I didn't know that there are 6 brake lines though, will need to do some Googling to see where the 5th & 6th lines go.

Any recommendations on brake fluid? It's always had standard Bmw DOT 4, am thinking about putting synthetic Castrol React SRF in it which has boling points of 608 Fahrenheit dry & 518 wet as opposed to 509 & 338, that can only be better....right?

Edit: The SRF is £50 a litre & seems like it's for competition use, so am not going to put the put that in it.

A bit more research shows genuine Bmw DOT 4 boiling point is 509/265 Celsius, same as Castrol react.
Anyone used anything with higher boiling temps?

[Chappers 71]

Originally Posted by mjn77

No fade with EBC grooved discs and yellow stuff pads.

I never had fade with the red stuffs but am fairly sure they ate 3 pairs of front discs though.

[Tambohamilton]

5 & 6 go between the chassis and rear subframe.

Yes, best to get fluid for road use in there...not sure really what the difference is though, as race fluid has better specs?

[Chappers 71]

Am considering buying a set of Brembo HP2000 ceramics for the front, anyone tried them?
Am curious if these will also ruin the front discs. After getting through 2 new pairs of front discs whilst using red stuff pads I've had no steering wheel judder issues under braking with the current ATE discs with standard Brembo pads & I don't really want to change the discs to drilled or slotted/dimpled as I like the OEM look on a SE car.

[Chappers 71]

Originally Posted by Tambohamilton

5 & 6 go between the chassis and rear subframe.

Yes, best to get fluid for road use in there...not sure really what the difference is though, as race fluid has better specs?

Thanks

Looking through the service records it appears that I took it to my local STS for its last brake fluid change & they wouldn't have put genuine Bmw DOT 4 in there, most likely some less expensive stuff that meets minimum requirements of 230 degrees C dry & 155 wet.

Will most likely put the fully synthetic Castrol React in there which is 265 dry & 180 wet, Bmw DOT 4 is 260 & 170.

[nomiS330d]

I got an advisory for my front brake pipes last mot. I changed the fluid a couple of years ago which firmed the peddle up nicely, can’t remember what fluid I used, just Halfords dot 4 I think. I too am going to change my hoses for braided. Got a few saved in ‘my eBay’.

[Chappers 71]

Bought 2 litres of Castrol React today & hopefully the hoses will arrive tomorrow or Saturday.
Once the hoses & fluids get changed I'll see how it feels before deciding on the pads.

[nomiS330d]

Which hoses have you gone for?

[Chappers 71]

Originally Posted by nomiS330d

Which hoses have you gone for?

After a fair bit of looking I went with the 6 line kit from Proline, their website looked ok & they were surprisingly inexpensive @ £83.45 including 1st Class signed for post, considering their kit does all 6 hoses.

Link attached

https://www.google.com/url?sa=t&sour...qyv9-hVLXYPLpw

Will post up pics & 1st impressions when they arrive.

[nomiS330d]

Originally Posted by Chappers 71

After a fair bit of looking I went with the 6 line kit from Proline, their website looked ok & they were surprisingly inexpensive @ £83.45 including 1st Class signed for post, considering their kit does all 6 hoses.

Link attached

https://www.google.com/url?sa=t&sour...qyv9-hVLXYPLpw

Will post up pics & 1st impressions when the arrive.

I’ve seen those and a few other kits on eBay all for about that price. I’ll be interested to read your thoughts on them.

[Chappers 71]

The new hoses arrived today & they seem to be fine, although I have nothing to compare them to.
They have a nice weighty feel to them, the fittings are all stainless steel & the hoses are Teflon lined stainless steel with some sort of plastic sleeve which is available in various colours.
Am happy enough with them, will post up when they’re fitted.

[mjn77]

The 5th and 6th hoses are a bitch to fit.

[Chapperss]

They look great - Not expensive either.

Be very interested to see if you notice any difference when driving hard.

[adammcf]

I use RBF600 fluid in my cars and bikes and its great for dealing with high temps without fade.

https://www.opieoils.co.uk/p-894-mot...-4-rbf600.aspx

[Chappers 71]

Originally Posted by mjn77

The 5th and 6th hoses are a bitch to fit.

Only if your fitting them yourself

[Chappers 71]

New brake lines & fluid done, also had both the front anti roll bar linkages replaced, will get an alignment done at the weekend.
Labour to fit the new lines, change the brake fluid & supply & fit the anti roll bar linkages £210

I haven't driven it yet, will most likely take it out tomorrow for a quick spin.

[Chappers 71]

Took the 35i out this afternoon, only did around 5 miles with a bit of duel carriageway & there's a definite improvement in pedal feel, a lot firmer so am happy with the lines & fluid change & the lines looked pretty neat, so yeah early days but I think for less than £85 for the lines is very good, the fluids just a serviceable item but at £24 for 2 litres works out at only £1 a month

The original hoses didn't look to bad but we're apparently a pita to get off, needed cutting & heat & as mjn77 predicted the middle hoses were the most difficult to fit

I still think there's something not quite right with how it's stopping though, not sure if getting the pads as hot as I did has caused permanent damage to them or if they'll clean up as I've done less than 50 miles since cooking them.

I also feel that I've lost confidence in the non ceramic pads & yes I probably shouldn't have put myself in a situation where I needed to brake so hard from the speed I was doing....but if as a scenario I was on a'private' road & had to brake from a similar speed to a stop I would like to feel confident that the car would stop & still have usable brakes.
Never had issues with the red stuffs fading no matter how hard I used them.

Will give it a couple of hundred miles or so & see if they improve, need to make a decision soon as the rear pads will need changing shortly.