# Front Disc Upgrade?



## Keviny (May 1, 2017)

Hi 

I have a 1990 B644 2.5TD Peugeot motorhome, based on the Ducato. It has the standard front brakes which are in good condition ( recent new pads, calipers/discs are good and recent MOT passed easily) but barely adequate, performance wise in modern traffic.

Has anybody upgraded to vented front discs and what did they use?

The other but cheaper option is to upgrade to a superior performance pad, has anybody done this?

I will do all the work myself as I have plenty experience, tools and time to do it.

Regards

Kevin


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## p-c (Oct 27, 2007)

Hi Kevin

I;m sorry that I can;t answer your actual question, but have you considered that you are driving a near top of its weight van of with nearly 30 year old technology and specification. Prempt the traffic flow in front of you and brake sooner and more gently.

It is not a new car.

Sorry if I offend.

Regards

p-c


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## Mrplodd (Mar 4, 2008)

A ventilated disc will NOT give you any better braking performance (in every-day use) 

What ventilated discs do is cool a bit quicker than non ventilated discs, that's why they are fitted to performance cars etc where the brakes are likely to get much harsher use than on a family saloon. Ventilated discs will not give any sort of benefit on a MH because (hopefully!) you will not be abusing your brakes that much so the don't need any additional cooling.
The same pretty much applies to "competition" brake pads, they actually give lower braking performance at lower brake temperature (which yours will be at unless descending a long downhill with your foot on the brake) but what they DO do is not "fade" (lose their braking ability) when they get hotter than those in normal use.

As p-c has alluded to, you have 30 year old technology to deal with. It's highly unlikely you will be able to find any ventilated discs or uprated pads for your MH.

Just a thought but is the brake servo working correctly?? To check it switch the engine off and pump your brake pedal until it feels solid. Keep your foot on the brake pedal and start the engine. You SHOULD feel the brake pedal being pulled downwards. If you don't then your servo isn't doing its job!

Hope that helps.

Andy


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## Keviny (May 1, 2017)

*Thanks*

I don't offend that easily and welcome all sensible comments!

I know the age of my vehicle carries the braking technology when it was built and that it really doesn't have the sports car performance which, if there, I would use as a 57 year retired mechanical engineer. Its really the other road users who pull out on you and other crazy things that they do that is inspiring me to try and improve the braking performance.

The vented disc will improve braking performance as it allows the brakes to work at an optimal temperature and frictional coefficient for both the disc and pad material. It's not the speed of my high performance vehicle that causing the high temperatures and subsequent loss in braking performance, its the descent of hills such as Cromford hill (Peak District) at around 1:17 over 2 miles thats causing the brake performance I experience. These descents necessitate the application of pad pressure over a long period with no recovery cooling time.

So I think vented discs would probably help or maybe to increase the braking area by fitting greater diameter discs, but that would probably necessitate different callipers (as would vented discs) and different wheels.

So still trying to find anybody who has improved the standard braking performance by either :-
A) Fitting high-performance pads
B) Fitting Vented discs
c) Fitting larger diameter discs

Regards

Kevin


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## p-c (Oct 27, 2007)

Hi Kevin

You are extremely correct about hills being the undoing of most motorhome brakes. I think all motorhomers have come across that one.

What I and most do is take it quite slowly, regardless of the traffic behind, use the gears and I have certainly, in the Alps, pulled in at appropriate opportunities, to allow cooling off time and for any traffic to pass.

If you do alter your brakes, inform your insurance company.

Regards

p-c


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## Mrplodd (Mar 4, 2008)

Have you checked the servo is actually working??

Also p-c is correct, if you are on such a long downhill section you most certainly should NOT be braking all the time but using as low a gear as necessary to keep your speed regulated and ONLY braking when necessary to reduce your speed further. 

As for the ventilated or non ventilated disc issue a vented disc will NOT improve the braking efficiency if some idiot pulls out in front of you but it WOULD enable to apply your brakes for longer before experiencing brake fade whilst on the 2 mile hill you have referred to (although that is a very bad practice) 

Andy


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## erneboy (Feb 8, 2007)

Doubtful you can get or fit bigger discs (along with calipers and pads to suit). The size of the disc and calliper are limited by the space they have to fit in and are usually close to as big as will fit. You'd probably upset the balance anyway.


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## Pudsey_Bear (Sep 25, 2008)

I would check the servo and it's pipe, also the flexi pipes going to the calipers, ovality of the rear drums, and the load sensing mechanics, also when was the brake fluid last changed, make good use of the lower gears when going down hill, I tend to drop to 20/30 on seriously steep hills, sod the traffic behind, and let the speed creep up then brake back down, do this a few times rather than trying to brake all the way down, sorry to teach you to suck eggs, but we don't know other peoples ability or driving knowledge.


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## havingfun (Oct 31, 2007)

Hi,
you could try this company I used to improve the front braking on my 2001 fiat ducato they modify standard disks with their cnc machinery by drilling and groving give them a call or look them up on Ebay I found them very helpful.Bernard 
A TO Z MOTOR SPARES
A TO Z MOTOR SPARES WAKEFIELD
6 LAWEFIELD PARK
WEST YORKSHIRE
WAKEFIELD
West Yorkshire
WF2 8ST
United Kingdom

Phone:01924|369000
Email:[email protected]


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## Pudsey_Bear (Sep 25, 2008)

I was of the opinion that drilling or grooving brake discs only improved wet weather performance, as you actually reduce the braking surface area.


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## Pudsey_Bear (Sep 25, 2008)

Could work either way it seems.


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## drcotts (Feb 23, 2006)

Just be wary of modifying anything away from factory fitted specifications lest you void your insurance. 

If you do upgrade get some sort of warranty or something to convince the authorities that its a bona fide retro fittable part.

Many years ago i fitted what was supposed to be a TUV approved air bag system to my old glendale. It was nothing like TUV approved and would have been a problem as the brake compensation valve that should have been supplied was an optional extra when it should have been supplied with the equipment.

So just be careful when messing about with brakes..please


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## Big Paul (Dec 28, 2017)

Hi, had an interesting two weeks in Corsica, with lots of very long, steep and winding hills ( proper mountain goat stuff ! ). Lots of brake fade and I thought, possibly boiled oil!!! So when I returned I spoke to an ex pro rally driver friend who suggested that I use ‘competition’ brake fluid ! 40 quid later and 2years later and no more braking probs. Def worth a go. Good luck, Big Paul


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## powerplus (Oct 6, 2014)

so from the video clip gas may be a problem


barry


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## Mrplodd (Mar 4, 2008)

Big Paul said:


> Hi, had an interesting two weeks in Corsica, with lots of very long, steep and winding hills ( proper mountain goat stuff ! ). Lots of brake fade and I thought, possibly boiled oil!!! So when I returned I spoke to an ex pro rally driver friend who suggested that I use 'competition' brake fluid ! 40 quid later and 2years later and no more braking probs. Def worth a go. Good luck, Big Paul


Brake "fade" is caused by the friction material on the brake pad getting to a very high temperature and losing its coefficient of friction with the brake disc. (Think back a few years to when lorries had drum brakes rather than disc brakes. On long downhill grades it was necessary to select a low gear BEFORE starting the descent, otherwise the brakes would get really hot, fade, and the lorry ended up with no brakes) The harder you press the brake peddle in such circumstances the hotter the brake pad gets, the MORE fade you get, its a VERY vicious circle. "Competition" brake fluid will NOT stop that happening, what it will do is have a higher (temperature) boiling point, thus if the brakes get really hot it is less likely to boil and introduce gas into the hydraulic system. Once you have gas in the system you will have a very "spongy" feeling brake pedal that may well go all the way to the floor without applying much brake pressure. Brake fade caused by overheating disappears once everything has cooled down a bit BUT if the brake fluid has boiled the gas released stays in a gaseous form and the only option is to bleed the brakes tom get the air out.

Brake fade is very common on caravans on long downhill slopes. The car driver selects a low gear to save the car brakes BUT caravans have over-run brakes so will be applied for the whole time!!

See the below link to a brake manufacturers website that explains it.

https://ebcbrakes.com/articles/what-is-brake-fade/

Andy


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## trek (May 1, 2005)

When was the brake fluid changed ? 

And by that i mean flushed through to each wheel cylinder which i suspect manu garages are not doing this these days my suspicion is they only replace the fluid in the reservoir by draining through the one wheel cylinder underneath it normally the front drivers side

The times i have taken vehicles back to dealer after a fluid change because i can find no evidence of disturbance at the other three wheels
I.e the rubber dust covers havent been removed except the one under the reservoir easy to see !


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## Mrplodd (Mar 4, 2008)

trek said:


> When was the brake fluid changed ?


Read post number 13 !

Andy


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## trek (May 1, 2005)

Mrplodd said:


> Read post number 13 !
> 
> Andy


What about post nos 13 by BigPaul ( he is suggesting competition fluid )

My question was directed at Post no 1 by Keviny as their fluid may be many years old and in need of a change as many people dont bother and it could have absorbed a lot of moisture over the years and have all that black gunk at the cylinders

so a fresh flush with standard fluid could possibly assist and negate the need for any special fluid


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## Pudsey_Bear (Sep 25, 2008)

The cost of the fluid is negligible, it's the labour which is expensive so why not got to at least dot 4 at the same time, at least eliminating the hygroscopic fluid, fit better pads and most of the problem is gone, another issue is people who do not use the gearbox properly and drive on the brakes down hill, we have an automatic car, but I change down manually on really steep hills not needing to touch the brakes at all usually.


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