brake fluid top up
 

Hello
Have a zt 1.8 53 plate. Just giving it a 6 month service. Just looking if in anything needs topping up. Notice brake/clutch fluid is about 10 mil below Max. Discs n pads were replaced 6 months ago does this sound ok? Should I top it up, if so should I use just normal dot 4 fluid. Thanks

It should be OK to top it up and keep an eye on the level for a while.If the level drops again you'd need to check for leaks.

Some might advise just leaving it as is and keeping an eye on it. One suggestion is that the level should be set to max when new pads all round are fitted, then you have a guide to how the pads are wearing by the fluid level. Fit new pads and the level will come back up to the max.

If you keep topping it up as the pads wear, then have to fit new pads, it will then overflow.

I agree with HarryM1BYT - that's a very good way of checking pad wear.

Obviously of course you don't let it get too close to the minimum mark.

Dont forget to make sure the brake fluid is changed regularly. Its the most forgotten service item on a car. If changed regularly ALL the brake components will outlast the car. Why wait for calipers to seize before doing anything and the cost of repair will far exceed the cost of regualr fluid changes. This does not of courese apply to brake pipe corrosion which can be stopped with a coating of water pump grease. I always grease the brake pipes when I see one. Again a 10 minute job to stop hundreds of pounds in pipe replacing.

Thanks for the advice, had the car 6 months now and can't find any evidence of a brake fluid change, so will be getting this done on Tuesday.

The standard replacement schedule for the brake fluid (DOT4) is every 2 years/30K miles, which ever occurs first. This involves flushing out the entire reservoir contents via the caliper bleed valves and replacing with fresh fluid via the reservoir, without allowing any air into the master cylinder. There are various methods of driving the fluid through the system (pedal pumping, external pressure pumping or vacuum pumping). Some say the ABS module must also be purged, but that's outside the scope of DIY servicing and frankly, I doubt many garages are capable either.

TC

I've read a lot about spongy pedals and purging the ABS unit. I dont understand this as I've changed brake fluid dozens of times for getting on for 50 years and never had a problem. Isn't this a case of not topping the reservoir up and getting air in the system or never changing the brake fluid? Just how how does air get in the system if not for these reasons? Little while ago, put all new discs on and all new fluid and no spongy pedal.