Brakes drag

[gafiredog]

My 78 dually has new brakes in the front. new calipers, pads, hoses, all have been replaced. I installed new shoes on the passenger side in the rear along with a new wheel cylinder, I don't drive it that often, but here lately, the brakes won't release fully, it feels like i'm driving down the road with my foot slightly pressed on the brake pedal. any ideas???? I can't find anything out of place.

[cjthompson]

Does it seem isolated to one corner of the truck or all around just not releasing?

[gafiredog]

Originally Posted by cjthompson

Does it seem isolated to one corner of the truck or all around just not releasing?

seems to be all around, but not sure. when I get on the brakes hard, the left rear will lock up.

[cjthompson]

My dad just got through struggling with a similar issue on his 1 ton. Ended up being a combination of the proportion valve and a rubber line pinching.

[barry1982]

Hi There,

You said you only changed the passenger rear brakes....but not the drivers rear? Did you inspect the brakes on the drivers rear? I'm not sure about 1 ton's.... but 1/2 and 3/4 are famous for rear axel seals leaking gear oil into your brake drums. The shoes soak up the oil, and swell which could be why that wheel is braking harder. Like I said, I'm not sure if 1 tons have this issue, but I have changed a whole lot of axel seals/ brake shoes in old Chevy trucks.

[gafiredog]

Originally Posted by barry1982

Hi There,

You said you only changed the passenger rear brakes....but not the drivers rear? Did you inspect the brakes on the drivers rear? I'm not sure about 1 ton's.... but 1/2 and 3/4 are famous for rear axel seals leaking gear oil into your brake drums. The shoes soak up the oil, and swell which could be why that wheel is braking harder. Like I said, I'm not sure if 1 tons have this issue, but I have changed a whole lot of axel seals/ brake shoes in old Chevy trucks.

thanks guys, I tried to drive it today and the brakes are almost locked down. I'm thinking a bad proportion valve also. the rubber lines to the calipers are new. the only reason I haven't done the drivers side rear brakes was i just ran out of time that day, but will get back on it tomorrow. btw, I did replace the seal in the passenger side due to leaking. thanks for the help guys.

[raceman6135]

Some other possibilities:

- rear shoes were not adjusted properly: one could be tighter than the other, or they both could be set up too tight

- rear flex hose could be swollen inside, which will hold pressure to the rear brake cylinders

- emergency/parking brake cables can be seizing and pulling on the shoes - I had this happen to me, even though I never used the emergency/parking brake

Let us know what you eventually find.