Spent most of today installing new front brakes on my wife's 67 Mustang. It has manual front drums (we're keeping it original). Installed new drums, new bearings/races, new shoes, all new hardware, new brake hoses, new wheel cylinders. All new parts from NPD. Adjusted/bled with a good pedal. These things shudder bad. Anyone had problems with having to machine new drums out of the box? Only thing I can think of that would cause it. Any thoughts or experience with this?!
I have the same problem. We're hoping, in our case, that it's the brake fluid that spilled on the shoes.
The shoes may have to arched to the drums. The center of the shoe should hit the drum first and then the ends next.Probably isn't anyone out there that knows that shit anymore. Try to find a grey beard. I've used a BFH to do this before, years ago
Shuddering is a good sign of out of round drums. Back in the day when we sold new drums over the counter to a car owner we always would give them a skim to be sure the were round. Most shops had their own lathes so didn't bother with those.
Thanks guys! I'll pull them tomorrow and run them up for a turn/machine to ensure they're round. In fact, I'll make it a point to ask him to check them as he's starting to see how bad they were.
This just happened on my wife's '98 Bonneville drums in the rear.. I just took it for a high speed ride and did some hard braking to seat the shoes. They are fine now.
alot of shops do machine before installing. most cases you can get away with just putting them on. sounds like they may have been dropped in shipping, or some time they sit on a shelf to long they get shelf warp or were not stored right... maching them is the only fix. ask who cuts them to tell you how much run out they have.
John Evans, posted above, hit it exactly right. While that may not be your problem, in my fifty years experience in the business, I always "skim" turned new drums and almost all brake discs (rotors) and never had any problem. Also, always spray the linings/drums and/or pads/discs with "brake kleen" just before final installation.
I put a new set of Socal speed shop alum hide a disc kit on my 32 pu and it shuddered for a while. I was going to pull them off but it stopped, it just go's to show ya.--TV
Most of the drums tell you on the side of the box not to store them on their sides. Doon't know it happens but they become out of round. We always skim them at a friends shop and he wil cut the shoe to fit the drum.
Good information!! Getting ready to overhaul my 68s brakes like the O P. Now i'll check those brand-new drums before installation.
I always take a cut even on new drums before I install them. If yours were factory cut, I'd hazard a guess that maybe they weren't piloted off the bearing races, or who knows what happened to them. New drums should come with new races, if you change them, they should be cut again. When you do get yours re-cut, make sure they're not too finely finished, especially on fronts. I used to cut drums like yours on a #4 feed on Ammco lathes. Have them measured up first, I believe that you are allowed only a .090 oversize. Keep the fronts within .010 of each other size wise. Lastly, this is an old timer trick. Bevel the leading and trailing edges of your shoes slightly with a wood rasp to take away that sharp edge. They'll break in a lot faster. Watch out for anything like brake fluid or grease on the shoe surfaces, I'd always give the shoes a quick sanding with 60 grit before I buttoned them up. Bob
I've seen drums come in on pallets stacked every which way, so there goes the "store flat" caveat out the window. On arcing shoes, this is largely illegal in many areas and "over the counter" shoes don't have the extra meat on them to permit arcing to the drums. Of course someone always has a shoe grinder in a back room somewhere. Bob
One of the jobs I had as a kid in the 60's was turning drums in the auto parts store where I worked. I recall that most Ford front drums were staked to the studs and you had to use a cutter to remove them. Then I had to press the studs out, replace them, stake the new drum to the hub in a press with a die, then turn it it ensure it was round and square. I usually did all this while the customer waited. It didn't take that long. I can't remember for sure, but I think I was told that if you just slipped the front drum over the studs without staking them in place, the brakes would shudder. Might be worth verifying that if the drums turn out to be round and square.
Yesterday removed drums, had them checked. He turned them, but said they weren't bad, but he touched them up anyway. I square block sanded just a few strokes on the shoes to make sure there was nothing on them and no high spots. I also took advice on putting a bevel on the ends. Cleaned up, reinstalled everything, ensured adjusted. Test drove the car today and they are smooth as glass now. No shuddering, no grabbing, no pulling. Thanks VERY much for your help! Got it done and had time to play with the sudden death project car!
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