|
|
|
|
|
|
BMW Garage | BMW Meets | Register | Search | Today's Posts | Mark Forums Read |
|
BMW 3-Series (E90 E92) Forum
>
Brake fluid spec
|
|
08-12-2011, 07:56 PM | #1 |
Major
459
Rep 1,409
Posts |
Brake fluid spec
Car is due for a brake fluid change and I'm thinking of taking the opportunity to use a higher grade from the standard DOT 4.0(?). Any suggestions as to brand and grade?
|
08-13-2011, 03:28 AM | #2 |
Major General
268
Rep 9,915
Posts
Drives: VW T5
Join Date: Apr 2008
Location: Worcestershire
|
__________________
|
Appreciate
0
|
08-14-2011, 01:12 AM | #4 |
Colonel
118
Rep 2,216
Posts
Drives: E91 330d M Sport
Join Date: May 2010
Location: Stoke on Trent
|
Hmmm.
How do you use your car, and what other upgrades have you made to the braking system? For normal road use, there is absolutely no benefit using anything other than bog standard DOT4 from the nearest motor factor. If you track it, if you've upgraded to braided hoses, if you've got upgraded pads/discs/calipers and you expect to reach the point of brake fade, then you should think about using DOT5.1 instead. The main difference is the boiling point of the 2 types - DOT5.1 has a higher boiling point, but for normal road use this is almost completely irrelevant
__________________
Just how many Yorkshire sheep can you fit inside one exhaust?
|
Appreciate
0
|
08-15-2011, 02:54 AM | #6 |
Major General
268
Rep 9,915
Posts
Drives: VW T5
Join Date: Apr 2008
Location: Worcestershire
|
If a dealer does it will need 1 litre.
If it is done properly around 3 litres to flush it all properly.
__________________
|
Appreciate
0
|
08-15-2011, 12:46 PM | #7 | |
LSD - No, you're not seeing things
72
Rep 3,302
Posts |
Quote:
DOT ratings and boiling point do not go hand in hand. Motul RBF600 is DOT 4 fluid. dry boiling point of 312 °C / 593 °F wet boiling point 216 °C / 420 °F Motul DOT 5.1 fluid Dry boiling point 270 °C / 518 °F Wet boiling point 185 °C / 365 °F In my experience with tracking road cars, you can overheat old 'cheap' fluids easily. You can easily get to this point in on the road, mountian passes whilst on holiday come to mind... I have always found soft pedal (fluid boiled) sets in before I feel 'hard pedal but no brakes' - characteristic of overheated friction material. A soft or sinking pedal from overheated fluid normally won't recover and needs bleeding. New fluids will survive better than 12m old stuff in any case, hence the manufacturers 24m reccommendations. Anyhow, given the relatively small price premium of something akin to the RBF600 DOT4 (+£10) I would not bother with less in a powerful, heavy car. Just my 2p. You can flush quite easily with 1ltr of fluid. Just empty the reservior to within a few mm of the pickup so you dont pull air unneccesarily. The top up and bleed each corner. I did mine again recently.
__________________
Last edited by m1bjr; 08-15-2011 at 12:56 PM.. |
|
Appreciate
0
|
01-08-2012, 09:07 AM | #8 |
Colonel
58
Rep 2,398
Posts |
|
Appreciate
0
|
01-08-2012, 10:10 AM | #9 |
Zummerzet Zyder Drinker!
111
Rep 5,541
Posts
Drives: '06 330D Le Mans Blue
Join Date: May 2009
Location: Somerset
|
A stealer will attach a pressure bleeding device to the master cylinder and set it going - the monkey will then raise the car on ramp and open each bleed nipple in turn and will allow an "amount" of fluid to drain into a bleeding pot.
All depends how the tech does it and how much care is taken. A full bleed which will require diagnostic kit to be hooked up to the car which will fire the ABS solenoids etc will take far more fluid, but is rarely if ever done.
__________________
|
Appreciate
0
|
01-08-2012, 12:17 PM | #10 | |
Colonel
58
Rep 2,398
Posts |
Quote:
|
|
Appreciate
0
|
Bookmarks |
Thread Tools | Search this Thread |
|
|