New trailer toter, brake problems?

Got myself a new trailer puller. '86 GMC c7000. Goodwrench 366 with low miles. 6 good tires. $1000!
Problem is a couple of the brakes lock up.


Previous owner had already replaced the master cylinder and one rear caliper and hose.
Not sure if the problem is the caliper or bad hose. After brake locks up, I crack the bleeder and it releases easily.   Thinking if that caliper was bad it wouldn't release easily. That leads me to believe that the problem is the hose. I can get calipers from O'Reilly's for $78, so cost isn't bad. But don't want to spend the money if not necessary. Just wondering what your thoughts are on this.

that's a cool looking truck! old wrecker?

Is it just one wheel hanging up? If all is hanging up, the rod going to master cylinder needs shortened.   MACK

10 brakes are kinda important ,so please go over 100% of the system and get them working 100% right !If you don't feel 100% confident in loaning out the truck to someone you love, then get them brakes fixed !!

2) Where's the rest of the truck? LOL. I've never seen a 'short bed' dually before. It is a NEAT ride.

Jay

On a truck that old and you're going to replace the hoses anyway I'd surely replace the
calipers too for the price you mentioned

drums or  disc's ?          drum  probly drum to woren out  i.d.  stuck piston on wheel cyl. and or hardware                disc     caliper not  bleed out good or not floating

my guess would be hoes(s) first...

You really need to pull all the wheels and inspect the entire brake system. From personnel experience loosing brakes on even an empty heavy truck is scary. I lost brakes on a 6400 driving it home. The parking brake is less than useless for stoping even from slow speed.i didn't trust the truck so was going 30 at the most. I would replace every thing. Worn pads or worn disks will allow the puck to extend to far out of the caliper and it'll stick. Old brake hoses often collapse trapping fluid in the caliper. Worn brake drums or shoes won't self adjust and the shoes stick until you back up to release them. The one brake line along the inside of the left fram rail where it goes through the frame cross member tends to collect dirt and rust through. When your fluid is laying on the ground It's not stoping the truck.

you should be able to feel every tar strip on the road! lol

Couple of the trucks I used to drive just so you fellas know I understand the importance of brakes. I did the brake jobs on most of the fleet.
Actually I wish my new toy had air brakes. I can do most of them with my eyes closed.

For some years I drove a '65 F350 with a 390 under the hood, and 4 barrel carb. 5.13 rear axle and a NP transmission with a 6.3 granny gear. I never did determine a limit to its towing capability other than traction.

On day I took it to my farm just east of Ames and hitched up a sturdy hay rack and headed west and south towards Woodward to buy some 8" wide flange steel beams I wanted for house building. The engine and drive train had so much torque, dragging brakes weren't noticeable. Going west on IA 210 in Madrid on the jogs I heard a loud bang and looked back in the tall mirrors and saw a mushroom cloud blowing out of the left side of the truck from under the flat bed. The next place there was room to get the train off the road I stopped and found the inside sidewall of the inside right dual missing. Since I wasn't putting a load on the truck I figured one rear tire would carry the load adequately. And went on. I didn't have a spare. I thought I had brakes and headed back for the farm crossing the Des Moines River valley after loading about 80 feet of 35 pound per foot wide flange I beams. At the farm I unhitched the hay rack and dropped in on a neighbor. He noticed liquid dripping under the rear axle. I drove it 8 miles home and started digging in. When I pulled the right side wheels and drum I found the springs softened and no brake shoe linings at all, just soot. When I looked for brake shoes I found it was a 2 ton axle, not a 1 ton axle. The hose to the rear axle lining had come loose and kept the brakes from releasing. New springs, shoes, wheel bearings, and shoes plus that hose made it work again. Sometime I replaced the front hoses and found the '65 F350 hoses didn't fit the brake assemblies, it took '64 front hoses. A truck assembled from assorted pieces and the cab had more than a couple bondo spots.

When I bought it, the brakes worked once in a while but not every application. Fortunately the gears got it down to 2 mph in granny gear at idle. A new master cylinder fixed that intermittent brake problem. I put 6 new bias ply tires on it and I think I spent more on tires that I paid for the truck. At the tire shop the help wouldn't touch it because of the retainer ring rims so the boss did them all. I've never seen tire show help work so hard on other projects to avoid mine.

Gerald J.

I can understand the split rim fear. I worked at a Goodyear tire store early on in my career. The commercial tire guys did all of the split rims no matter the size. One time filling one up they had a ring come off and do serious damage to the cage. My best description is think about how loud the commercial fireworks that are only a white flash would be in close proximity. Pretty darn loud...

anyone that learns to drive with iffy or no brakes, will be able to drive anything they are put in!

well we want pics of it as you clean it up and modify it!