Rear Brake Lock up

[47to70]

Left home and thought the brake pedal was a bit high but am old and was tired and though it was just me. Picked up a load of hay and got ten miles down the road, looked out my rear-view mirror and saw smoke. Pulled off to the side and smoke was coming off all four rear wheels. Not much I could do on the side of the road but let them cool off and try and limp home. After 1/2 hour started down the road, stopped after 3 miles, no smoke. Went another 3 miles, stopped no smoke so decided to make a run for home. 10 more miles no smoke, brake pedal seemed normal, and brakes had released. I did a minor brake adjustment a few years ago and wonder if I did not over adjust them. It was a 90 degree day and all my driving has been in the cool of the morning. What else might cause all four rear brakes to drag or not release?

 

[Elk1111]

For it to be all four I’d guess it’s your air pack. It could probably use a good cleaning and rebuild.

 

[ToddJK]

I've had one brake stick before but not all four. @Big Tom , he had a good suggestion to see if it was the master cylinder or the air pack. Perhaps he'll see this and chime in.

 

[Big Tom]

If it was ONLY the back and not the front your problem is a bad brake hose from the frame to the back axle , they Collapse inside I do not let the food returned back but the pressure from the pedal will push it by causing it to be trapped
I have seen this many times it can happen to any brake hose

Big Tom

 

[47to70]

Ahso.....................sounds like a bad brake line.......................started the old gal up this A.M. and all was good. Your suggestion sounds right as this problem could come and go, and more liky to happen when it's hot. The air pack was replaced just before I got her, 6 years ago but only about 7000 miles ago. There are two rubber brake lines on the back...........would one bad cause both sets of wheels to lock up, or could they both have gone bad in at the same time?

 

[wiggall]

I've had one brake stick before but not all four. @Big Tom , he had a good suggestion to see if it was the master cylinder or the air pack. Perhaps he'll see this and chime in.

Crack the air line going to the air pack. Block the wheels before you do it.

 

[47to70]

With air pressure or not?

 

[rustystud]

Does this truck have dual air-packs ? The right side air-pack on a dual system operates the front brakes and the left side air-pack operates the rear brakes.

 

[47to70]

Rusty,

Am not sure of the difference, but it is the old style long air pack.

 

[rustystud]

Rusty,

Am not sure of the difference, but it is the old style long air pack.

So you don't have "two" air-packs" correct ?
Then I would look at both rear hoses as being bad. It's rare to have both hoses go at the same time, but this is an old truck.
Are you positive the front brakes are not locking up too ?

 

[47to70]

Rusty,

Yes, just one air pack. I felt the front hubs when she was acting up, they seemed just "normal" warm. Needed to move her yesterday A.M. and she rolled freely. Will order the two rear hoses and hope for the best and it's the cheapest fix. You're up early on a Saturday!

Thanks

 

[rustystud]

Rusty,

Yes, just one air pack. I felt the front hubs when she was acting up, they seemed just "normal" warm. Needed to move her yesterday A.M. and she rolled freely. Will order the two rear hoses and hope for the best and it's the cheapest fix. You're up early on a Saturday!

Thanks

Actually I'm up late !
I worked "swing shift" for the last 35 years before retiring. Cannot seem to get my body to adjust to "normal" hours now.

 

[wiggall]

Does this truck have dual air-packs ? The right side air-pack on a dual system operates the front brakes and the left side air-pack operates the rear brakes.

No single air pack.

 

[wiggall]

With air pressure or not?

With air pressure. I have to dump the air to get them to release.

 

[47to70]

Update, while waiting for the "flex" lines, pulled all the rear wheels using the caveman method. Shoes looked good, new grease, and adjust. Put new fuel filters on, old ones realy needed replaced (think that they caused the reae brakes to lockup...LOL). Today was cool, took her for a test drive, pedel felt fine, stopped on some mild grades and she rolled freely, no hot hubs. Best theory to me is the rear rubber hoses and a 90-degree day gave them all the excuse they needed to fail. Has anyone had an air pack fail.....come and go? Waiting for solder #2 (aka: #1 son) to show up next week so can put on new lines.