We are the original owners of a 1978 Z. In the past two years we have had a terrible problem with brake squeal. We are on the fifth set of brakes in two years trying to overcome the problem. We'll try most anything and will certainly appreciate any help.
Squeal is caused by a vibration as the pads are applied. You did not give much detail about your setup but generally:
1. You need the hardware that was stock including the shims and clips in place.
2. You need good linings that won't glaze up if used hard.
3. Everything in the caliper has to fit properly. Are the pins the right size for the appl.? I have rarely gotten the right parts from the catalog for this car. If I didn't have an old ones to compare, I would have been given the wrong pins.
4. Are the calipers worn where the pads bear?; did you clean and lube the bearing surface of the pads where they contact the caliper?
5. Are the rotors running true and are the wheel bearings adj. OK?
Don't ever use that spray-on Glop that is supposed to cure this problem. Fix it instead.
I had the same problem with the brakes on my 1978 Z. I bought a set of performance brake pads for Motorsport, part # 24-5501 for $ 27.95, and the squealing STOPED! Even if the car sits for a while it still does not squeal. Hope this helps.
Dissaemble your brakes by (A) keeping 'em on the hub (B) By removing the retaining pins (C) by removing the current front brake pads/shoes/discs. (D) Run your fingernail over the rotor facing the pads and check for any uneven surface to catch a fingernail, if so have the rotors 'turned' and if told not enough material to do so then just replace 'em. (E) Take the shims off and WD 'em. Find a chissel and scrape these shims to shinny bare metal. Note the direction they face to reinstall back on to the new brake pads you will be purchasing. (F) Put Liberal amounts of grease on the each side of the shims, espicially the sides facing the pistons. (G) Take a nail and carefully punch a hole into the rubber atop each piston on each caliper. (H) With your WD and its accompaning plastic straw you'll put the straw into these rubber holes ( very small ones...) and you'll release WD into the pistons in order to lubricate the pistons really well. (I) Take a large half-inch screwdriver and pry/push the pistons apart to get room to install your wider new brake pads. (J) Now simply re-install everything. Your pistons should not be hung up any longer if so before.....If rotors could catch a fingernail it was due to a frozen piston, brake squeals are from the same source of partially frozen piston resulting in very worn wear on generally only One pad at one caliper. The grease on the shims will prevent any further squeals .
Well hope you've had fun. Don't forget to bleed your brakes now. Goodluck. shane-
All the above are good suggestions...my 78 brakes SCREAMED!!!...turns out the problem was aftermarket "one-size-fits-all" crap parts...replaced with OEM and semi-mettalic pads...no squeals for 6 years (so far!!)... )
My experience is that if I did'nt use all the Nissan hardware (shims,clips,Etc..) thaT i GOT SQUEAL. Not fade. Ferrodo pads take care of that. Get all the kit from Nissan except for the pads and rotors.