Hi we have a 2006 KA 38,000mls, when braking really hard the car starts to pull up well except all the sudden pedal drops and loses braking which gives the impression its gone into a slide, I've checked discs/pads/hoses all are good and plenty of fluid, are there any other faults to look out for abs etc? Under normal driving conditions they work fine, any advice appreciated look forward to any solutions 

 

Unusual fault.

For the pedal to drop and lose all brakeforce under hard load but regain braking afterwards can really only be the ABS pump or the master cylinder.

I might be tempted to try the MC first if it's cheaper & easier than the ABS pump.

Could be the brake flexi hoses gone too (balooning, very rare but can happen) get someone to hold the brakes on, full pressure, with the engine running and see if you can see any of the hoses swelling