The Stovebolt Site Forums The Shop Area Driveline Truck braking?

My old 55' seems to be darting back and forth as I am hitting them there brakes. I readjusted them, rotated the tires, tightened everthing up, replaced the 2 brake hoses, thinking they might be internally falling apart. Don't really know what it might be? Brake shoes are new, drums were turned down, don't know?

If the shoes weren’t matched to the drums(rarely done now) they will be hitting on high spots until the shoe radius gets broken in to drum ID. That is assuming no fluid on drums.

Ed

As Ed says, if your drums were turned and your shoes are new, there will be two slightly different sized circles you're dealing with now and simple geometry tells us only the high points of the inner circle will hit the drums now. This will take care of itself in time and often doesn't produce the result you're talking about but a failed or failing wheel cylinder (usually in the front) can. It causes the side with the good cylinder to want to stop while the other side (which has the bad cylinder) not to want to stop. Just a thought. Sounds to me like something is causing the brakes on your front to work unevenly and this is a good culprit. This same situation on the rear might not be felt as much...usually on a vehicle like the AD it feels like your brakes aren't working as well anymore when one cylinder on the rear fails (which is exactly what is happening). I think if you didn't replace or rebuild the wheel cylinders on the front, I'd do that now. There are some wheel cylinders and master cylinders still being made in the USA. One brand the master cylinders are being sold under is Cardone. The wheel cylinders interestingly are being sold under the AC Delco name. Rock Auto has them for about $30 each last time I looked. Hunt for the "professional" model. You can usually find rebuild kits also at Rock Auto. Good luck.

Start looking for worn or damaged steering and/or suspension components instead of chasing brake problems which probably don't exist. A loose steering gear center point adjustment would be a good place to begin, followed by a check of wheel bearing preload and kingpin slack. Even sloppy bushings and shackles on the rear springs can let the rear axle shift and giuve you some oddball steering input.
Jerry

I agree with Jerry. The greater percentage of brake issues will have you pulling from one side or the other, not wandering. Take it for a drive and see if it wanders without applying the brakes. It could be that your brake application is just amplifying what issue was already there. Then check your steering/suspension components. Check for tire separation/tire issues.

OP’s post 1 explanation:

“My old 55' seems to be darting back and forth as I am hitting them there brakes.”

One brake is likely getting pressure first........other items not mentioned that effect pressure are the lines both steel and rubber full of rust, partial blockage or severe restrictions.


Even a modern car or truck witha a stuck or stiff caliper piston or slides will cause the dart or drift on first brake application. Drums are far more sensitive to shoe travel, shoe contact points. Adjust the shoes until they are just off of dragging and test drive. Jack the front up , have assistant touch the brake check the wheel rotation, try multiple brake pedal pressures to isolate the wheel that too tight or too loose on rotation.

Mark is probably correct. [on edit] Jerry also got there first (as usual.)
Loose steering/suspension components could cause that. With a different load on those components with brakes applied, the steering geometry could be affected. A Model A I had would sometimes exhibit "death wobble", but applying the brakes would eliminate it. This would be similar but opposite. Maybe toe-in is changing enough with brakes applied to cause the wandering.

I agree with all the possibilities with regard to steering & suspension issues but I would remove all wheels & brake drums and do a sanity check to be sure that something isn't installed wrong, a spring broke or became disconnected, a shoe delaminated, or a seal or cylinder started leaking. Any number of things can go wrong in there. And as many here know, just because you installed new parts doesn't insure they are any good.
Fred

First off I want to thank you Bolters for your reply's, This here week end I plan to tear into it. I have messed around with steering boxes before, although it has been a while clue me in here on just where I start with this here steering box to tighten her up a bit. I had it on stands and the steering seems a tad loose, I am thinking this is one place I want to look at...᠁ Thank you.....

I don't think I'd mess with the steering box until you've checked everything else. You can check it by disconnecting the drag link and checking for play in the pitman arm. There are a lot more items that will affect steering play besides the box.
Do you still have the barrel type tie-rod ends that are adjustable? I'd start there if you do.

That is the best place to start any diagnoses! With a visual inspection!