Home > Td5 > Brake fade |
|
|
custom90 Member Since: 21 Jan 2010 Location: South West, England. Posts: 20348 |
When was brake fluid changed / checked?
|
||
26th Oct 2015 9:34pm |
|
couplands Member Since: 31 Aug 2011 Location: Peak District & Cornwall Posts: 1826 |
^^^^ at the same time as the discs/callipers were changed. I also had to swap the ABS unit so got through a lot of fluid doing the bleed process.
But might be worth doing again... cheers simon |
||
26th Oct 2015 9:37pm |
|
custom90 Member Since: 21 Jan 2010 Location: South West, England. Posts: 20348 |
Maybe air in the fluid, sounds a bit like it needs bleeding possibly.
|
||
26th Oct 2015 9:41pm |
|
isacs Member Since: 28 Aug 2015 Location: Leamington spa Posts: 404 |
What dot fluid was used? If only 4 then swapping to 5 might help as it has a higher boiling point. And get rid of the standard flexible hoses and fit stainless braided lines. That's normally what causes brake fade after prolonged use.
|
||
26th Oct 2015 9:46pm |
|
couplands Member Since: 31 Aug 2011 Location: Peak District & Cornwall Posts: 1826 |
^^^^ I've seen DOT5.1 mentioned on other posts, so might give it a go. I used DOT 4 when I replaced it previously. And the flexible pipes might be a good shout. The truck has only done 36k miles, but its 14 yrs old, so worth putting some braided flexies on.
|
||
26th Oct 2015 9:50pm |
|
Lambley Member Since: 20 Apr 2013 Location: Mid Devon Posts: 1435 |
Have you checked the master cylinder for cracks, it's a common problem and happened to me a while back, swapped the master cylinder and the difference was amazing!
http://www.defender2.net/forum/topic34628....p;start=15 Look at the picture with the arrow from NickH |
||
26th Oct 2015 9:57pm |
|
couplands Member Since: 31 Aug 2011 Location: Peak District & Cornwall Posts: 1826 |
^^^ I'll check for the crack, but as I said earlier, the brakes work well until the fade sets in. So 99% of the time they are rock solid.
The other option is to remove some of the kit I carry, its just damn heavy..! |
||
26th Oct 2015 10:00pm |
|
custom90 Member Since: 21 Jan 2010 Location: South West, England. Posts: 20348 |
What sort of gradients are we talking?
Mine did this once and only once on a extremely long steep hill, No real load either. |
||
26th Oct 2015 10:13pm |
|
couplands Member Since: 31 Aug 2011 Location: Peak District & Cornwall Posts: 1826 |
I would say the downhill sections were fairly long and needed prolonged braking. My 90 has solid discs and I've seen lots of other threads saying they are prone to fade when towing or carry heavy loads downhill, so it seems a resonantly common occurrence under these conditions.
I guess what I want is the kit list to upgrade to vented discs as per those fitted to the 110. |
||
26th Oct 2015 10:27pm |
|
Lambley Member Since: 20 Apr 2013 Location: Mid Devon Posts: 1435 |
^^^ I bought a set of take off 110 vented discs and calipers ( I think I got them from LRI) a couple of years ago, dead easy to fit, the pads you have will drop straight in, only other thing you'll need is a pin kit for the wider calipers. It does make the brakes better and less prone to fade but don't expect to be head butting the screen.
I'd make sure you check the master cylinder carefully before though, check around the bolts as the crack can be very small, mine had only done about 35k miles when I noticed it, it must have been like that for some time and I'd just got used to lit, but afterwards I realised how 'decent' they can be. |
||
27th Oct 2015 3:51am |
|
landy andy Member Since: 15 Feb 2009 Location: Ware, Herts Posts: 5695 |
When I up graded mine I just brought new vented calipers and discs, but bit of a shame as yours are new. Don't wish to offend, but shouldn't you engine brake more?
|
||
27th Oct 2015 8:02am |
|
roel Member Since: 08 Aug 2009 Location: Lelystad Posts: 2039 |
I had non vented discs on my Camel Trophy Discovery that was 2500 kg empty. On longer downhills (no not in Holland but France and Austria) I got my brakes stinking and smoking hot but never had problems with brake fade. What I would say changing to vented discs will not work against brake fade. You have to search somewhere else.
So brake fluid and hoses would be the first thing to look at. Roel 1984 90 2.5 na Diesel - RR V8 (1994-2001) 1997 Camel Trophy Discovery 300TDI (2001-2009) 2005 G4 Discovery III 4.4 V8 (2008-2018) It's gone but it still hurts. 2003 90 Td5 (2009-now) |
||
28th Oct 2015 1:36pm |
|
jimbob7 Member Since: 06 Jul 2013 Location: uk Posts: 2055 |
Simply buy vented calipers and discs,dont buy them from lr,100% cheaper from everywhere else,(they are AP calipers,not hard to find).tbh,non AP caliper bodies come from the same mold,they just have the AP name ground off.Pistons and seals can be supplied by anyone tho,stainless or not.As said, what are your driving habits,approaching steep hills in a lower gear/speed helps a lot,also momentarily releasing the brakes helps cool the discs (obviously before brake fade sets in).
Also DOT 5 is Silicon based which is a BIG NO in most vehicles. 5.1 is glycol based but totally unnecessary in a Defender unless you travel everywhere at 100mph with a fully loaded trailer,in which case you have poor driving habits and need to slow down. Pov.spec,ftw. 2006, 110,TD5. |
||
28th Oct 2015 2:23pm |
|
tazmarkuk Member Since: 24 Jan 2012 Location: Birmingham Posts: 134 |
What is brake fade?
Brake fade is a term used to describe the partial or total loss of braking power used in a vehicle brake system. Brake fade occurs when the brake pad and the brake rotor no longer generate sufficient mutual friction to stop the vehicle at its preferred rate of deceleration and can happen on motorcycles cars and trucks. The brake pad in any brake system is designed to work at certain operating temperatures. Being made of many different formulations brake pads perform in very different ways under temperature. This certainly indicates the fitness of a brake pad for application and its general quality. There are however two very different kinds of brake fade. 1.Green fade or early life brake fade This is quite common and almost normal when new components are fitted. It is merely a settling down of the components after install and can be gone in a few brake applications. To minimise or avoid this effect it is wise to drive cautiously when new brakes are fitted and give yourself a little extra braking distance for the bedding in period. This can be anywhere up to 500 miles urban use.Let the brake pads seat to the rotors and then use the brakes positively on a quiet and safe road area to show them some heat energy and this will be gone a lot quicker. Some manufacturers now “Surface scorch” brake pads to avoid green fade. This process is called heat searing or scorching of brake pads. The process removes surface organics or volatiles totally. 2.Dynamic fade or in stop brake fade This is more serious and means that you have either chosen or been sold the wrong grade of pad for your vehicles or the pad quality is suspect. Dynamic brake fade, which is best described as loss of brake during the stop outside the bed in period, is dangerous and needs to be remedied. In early days of drum braked vehicles brake fade was more prevalent. Towing a caravan down a long descent often resulted in brake fade where the brake liners were actually vaporising inside the brake drum and traffic authorities even built vehicle run off sand traps as an emergency route for vehicles descending out of control. The advent of disc brakes which are better vented and employ modern technology brake materials improved this a lot but there are of course many different brake pad qualities and types on the world markets. These are of course Performance Brake Pads and are a serious consideration for track day and race use. Brake fade can also be caused by caliper drag. When brake fade occurs the brake pad is actually skidding on a film of gas created by the over heating of the constituents of the brake pad. This does not always mean a poor quality brake pad has been used and in performance use pads can fade due to overloading the brake pad compared to its design targets. Trackday driving is a typical example. A weekend warrior takes a street based car to a race track and drives at speeds not seen on the highway and brakes till his eyes pop out of his head at a corner instead of smoothly decelerating the vehicle into the corner as a professional race driver would do. This of course just kills the pad compound which it was not designed for. Brake temperatures shoot past 1000 degrees F and few standard brake pads will tolerate that. Brake pads that have more heat capability are required in such cases and also better ducting of air to cool the brake system is needed. Brake fade should not be confused with Fluid vapour lock. |
||
28th Oct 2015 8:38pm |
|
|
All times are GMT |
< Previous Topic | Next Topic > |
Posting Rules
|
Site Copyright © 2006-2024 Futuranet Ltd & Martin Lewis