The brakes on my 405 are a bit poor, Generally feeling dead. I recently replaced a brake drum on an astra and noticed how much better the brakes felt (less effort required)
The question is - do the brakes only feel better for a short period since the drum is not worn smooth yet?
Any other suggestions to sharpen up the brakes?
In message , 405 TD Estate writes
The rear brakes only provide about 20% of your total braking force so I wouldn't think you would notice much of an improvement.
Have your 405 brakes always felt poor or is it something you have noticed getting worse? It can be misleading to compare the brakes on different cars. The number of times I've almost had an accident at Stansted airport, returning from holiday after a couple of weeks in a hire car with good brakes. I then get into my Ford with its under servo'd brakes and almost sail through the first junction I come to :-) After a few miles I've adapted to the higher pedal force required and its fine.
It could be that the new brakes are properly adjusted whereas the old ones weren't. Drums and sharp brakes don't usually go together.
The handbrake is very poor though it can hold the car OK. - Hence I suspect that the rear brakes are the culprit...
The fronts are probably cr^p as well but I can get a new set of rear drums for 30 quid - vented disks will be a lot more. (could try new pads in the front though but I dont think they will improve anything)
Additionally when the car is heavily loaded I notice the brakes become worse - perhaps because the balancer valve is now using more rear brake?
I would expect normal brake balance to be 60:40 ish to the front (equal weight front and rear for an estate but more front brake to prevent oversteer) under light braking of course (which is mostly what I do)
Under heavier braking the balance valve should transfer more force to the front - I guess then that trying some heavier braking would tell me of the fronts are cr^p as well.
When I replaced the drums on an astra estate i noticed the brakes became much sharper - but dont know if they'll stay like that.
I could do with the brakes being better when loaded so improving the rears would be good...
Adjusting the rears properly will mean less pedal travel for them to start working.
If the brakes get progressively worse when the car is laden then either the brakes are too small for the task, crappy pads are fitted, the discs are worn or the fluid needs to be changed. You can probably get discs for 40-50 quid a pair. If everything else is ok then you could fit "fast road" pads which give good braking when warm but can be a bit scary for the first few stomps on the pedal.
Poor braking can also be a sign of stuck calipers or perished rubber hoses. A complete overhaul might be a good idea.
Doesn't necessarily follow. The rear brakes and handbrake use the same shoes, but different actuation of them. An ill-adjusted handbrake won't affect the rear foot brakes.
GSF don't list estate rear drums - only saloon at £25 each. They do list vented front disks - less than £19 each.
Or perhaps because the brakes are trying to slow more weight down...? Is there a balance valve fitted on a 405 estate?
Balance valves normally just shove more brakes to the back if there's more weight. No more, no less.
If the handbrakes poor, then chances are it's because the brakeshoe adjusters are seized, and not adjusting up properly. Which causes two problems if adjustment is far enough out. For the handbrake, it means lower efficiency, as the handbrake lever can then be pivotting past the optimum angle of 90degrees (vauxhalls on the other hand suffer badly from poor efficiency if over adjusted due to the lever getting no where near 90degrees). For the foot brake, it means more pedal travel, as the brake cylinder pistons have to move the shoes further before they contact the drum
Vented discs are pretty cheap now (unless you're stupid enough to shop at halfrauds). If the pads haven't been out for a while (year or more), then they could well be sticking in the calipers, which is quite a common cause of a poor brake pedal, and lack of bite.
Define Balance Valve (only balance valve I know, is used to control the movement of a hydraulic cylinder so it moves smoothly) They were fitted with a load compensating valve, which the lever may well be seized on.
A load compensating valve will still reduce brake force to the rear system under heavy braking. As the weight transfers to the front due to braking forces, the rear suspension rises, altering the load compensating valve.
Although if the self-adjusters are working properly they should be doing it for you?
My first thought on seeing this was that something else which had been disturbed while changing the drums on the other vehicle had probably led to better braking performance, for example a seized brake cylinder which had become unseized by being shoved about. I've known the brakes on a vehicle to go from spongy to sharp just by freeing up a rear brake cylinder.
Well that could just be the handbrake adjustment being cack.
Why 'probably'? Check pad and disc thickness to get a better idea. Personally I've never noticed disc thickness have a huge effect on braking efficiency as long as it's above the minimum. Pad thickness has a much bigger effect (in my experience) because it makes the difference between being snug back in the caliper or dangling out in fresh air. For maximum effect, try driving a car on which worn pads have only been changed on one side and watch it pull like a bastard to the side with the thicker pads.
Or there's just more mass to slow down?
See below. Did you change shoes as well? Could be just that you freed up a semi-seized caliper or got the shoe adjusters working properly so you got rid of a load of travel, nothing to do with the drum. Not-worn-in drums would normally be *less* effective due to reduced contact area, you would have thought.
...Or a seized cable.
Handbrake feels solid and no stiffness until the shoes hit the drum - also the lever position is good - maybe a bit wooden feel and lack of power.
Who are GSF? - that's v.cheap disks!
I'll try to check this (looking underneath the car up at the handbrake I assume..)
Yes will check again - front drivers side was sticking last year.
Yes that's what I meant and how I understand it works.
Take a guess...
Also try
I dont seem able to find any vauxhall parts on their website!
Can you search for parts? the online shop doesn't list Vaux parts... ?
Adrian wrote:
Top of the front page of the website...
Welcome to GSF Car Parts Discount Car Parts for
Volkswagen Renault Audi Seat New Mini Mercedes Citroen BMW Saab Smart Car Porsche Peugeot Volvo Skoda
Nope, I don't see Vauxhall in that list...
In message , Adrian writes
Strange... it seems that they only do spares for German, Swedish and French cars. They really ought to make that more clear.
Would you consider an Opel to be German?
The message from Paul Giverin contains these words:
You mean call themselves "GSF (no really) Ltd"?
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