Brake Issues

[CA180]

Hey guys, i haven't been around in a while... I've had quite a bit going on... plus bunches of other projects!

Any how...

I have a 72 bump, upgraded to one of the "pivot" style boosters from an early dent. That works fine, or at least as far as I can tell. This thing has all around drums (that I soon plan on upgrading to front disks).

Here's my problem.
The brakes are extremely fussy! When I tap the pedal a little too hard the suckers lock down, but if I ease into it they seem to work OK. But if I'm coming up to a red light slowly and come to a stop then let off to roll up a little then stop again it feels like there is no brakes at all. Kinda like standing on the pedal and it goes to the floor and doesn't stop at all.

Now I was lucky enough that the previous owner had recently had the brakes redone and never really drove the truck. The shoes are nice and thick, the drums look almost new (no scoring or anything), brand new rubber hoses all around. And they are adjusted properly and were cleaned not too long ago.

Now my wife has been nagging me lately to let her drive it because I basically bought it for her, but I feel tremendously uncomfortable letting her drive it cause it seems so dangerous. Crap, I even feel a little nervous driving it myself and I'm used to old trucks!

So, anyways, after my long winded post... What do you think?

Does it sound like a bad booster? Or just the overall crappyness of front drums? Or all of the above?

Would disks remedy my woes?

Thanks in advance! You guys have always been so helpful! I love this place!

[montana_hiboy]

did the po replace the wheel cylinders when he put on new shoes, drums and hoses, how's the fluid level in your master cylinder, if everything checks out ok there i'd suspect the booster

[CA180]

Yeah, wheels cylinders look new... and fluid is full. No leaks at the four corners.

Right rear axle seal seams to have a very very slight leak, but nothing that should cause that type of an issue.

I'd kinda like to replace the booster with a year specific booster. But what I got was like $20 at the heap yard and we don't see many bumps round my area.

[390Nut]

Right rear axle seal seams to have a very very slight leak, but nothing that should cause that type of an issue.

I'd kinda like to replace the booster with a year specific booster. But what I got was like $20 at the heap yard and we don't see many bumps round my area.

A very slight dribble of gear oil was causing my rear-drivers side wheel to lock up long before the other wheels were close to doing there job. The brake shoes don't like greasy oily stuff getting in there. Get your seal replaced, and put new shoes on (and clean the drum, thoroughly) and I bet your problem goes away.

Did your truck have power brakes to begin with? Did you just add a booster to a non-power brake setup? Disk brake booster on a drum brake truck? (they are different internally, and the proportioning valves are different too).

[CA180]

Yeah, the truck didnt have power before. And yes it was from a disk truck, but I didnt change the master out. Just added the booster.

And as far as the axle leak goes, i'm not positive that would cause the front to lock up.

Hopefully this weekend will be nice and I'll have her out and about.

Thanks again

[fordman]

yes oily substances on the shoes will cause grabby brakes. since the leak is in the back that does not explain the grabby front brakes. i dont think a booster would cause this. maybe if the line to the booster was collasping it would cause the booster not to work properly but that would make the brakes harder to push if that happened. i would pull the front hubs and look at them and see what you can see. how is your brake light? check the bulb for proper operation. does it come on when you turn the key on? maybe you have an imbalance in the brake lines.

[CA180]

brake light doesnt come on, but i'm not positive that the bulb even works.

I'll update this weekend if I get any where with her.

[fordman]

you mmight try changing the bulb and see if it does come on when you turn the key on.