Replaced rear brakes - now 1 side hot & grabby

[Wickedstick]

Btw, THANKS FHR THE HELP!!!! Y’all have been throwing out some good info!

 

[Frank Enstein]

Have the shoe return springs been checked? New doesn't necessarily mean good. Compare the tension side to side.

If the ABS module is holding say 10-15 psi and the springs are weaker on the grabby side (which can be worse if it's been dragging and overheating) the good side wouldn't apply but the other could be dragging.

Also the shoes that have been dragging may be compromised.

Brake fluid leaked on the shoes will make them grabby as well.

Easy way to check? Spray the brake assembly with hot water.

If it looks white coming off the shoes that is an indicator of brake fluid leakage.

Disassemble the wheel cylinders and inspect for faults in machining/wear/disintegrating rubber seals.

New wheel cylinders (or anything for that matter) can have sub-standard materials/assembly/machining too.

Check the backing plates for grooves in the 3 raised pads where the shoes touch the backing plates.

Smooth them out (mine look polished when I'm done) and lightly lube the contact points using brake lube, making sure that no lube touches the friction material.

When I install shoes I polish the contact points on the shoe to smooth the edges to prevent them from making the backing plates "groovy".

I believe groovy backing plates are partially the fault of the hold down springs being too stuff.

Check the parking brake cables for binding/interference.

The solution will be something simple/overlooked.

 

[Wickedstick]

I will be double checking all of this again very shortly. All hardware is new, I haven’t checked tension between sides. Shoes are cooked at this point I’m sure but we’re new and replaced with the wheel cyl both times. Backing plates had small grooves but I hit those with a small barrel sander and lubed. I will have to look over wheel cyl and other components as well.

I appreciate all the insight and will post a solution when I find it so I can help someone else out on here!!!

 

[Wickedstick]

Guys I disconnected the EBrake cable at the joint between the front and back just under the doors on the drivers side. Took it for a 15 mile ride and same issue. Do I need to disconnect them inside the drum to truly see if that is the issue?

 

[Schurkey]

If it's the rear cable that's seized, disconnecting it ahead of the seized part won't fix anything.

If this were me, I'd pull the drum and see if the strut between the two shoes is actually pushing the shoes apart.

On Duo-Servo brakes, it's really easy. The top of the shoes should be resting on the anchor pin if the brakes aren't applied. If EITHER shoe isn't touching the anchor pin, the park brake is holding them apart; or the hydraulic system won't fully-release pressure.

With the terrible Leading/Trailing shoe design, you'd have to actually look at the park-brake/adjuster strut between the shoes, and the park brake lever coming up from the park brake cable. There should be a gap between the lever and the strut. The shoes will be held apart by the strut--which is also the brake adjuster. But the park brake lever shouldn't be pushing the shoes apart. There is no anchor pin at the top--there's an anchor block at the bottom, but both shoes ALWAYS touch the bottom anchor block. If there's a problem, it'll be at the top.

 

[Wickedstick]

If it's the rear cable that's seized, disconnecting it ahead of the seized part won't fix anything.

If this were me, I'd pull the drum and see if the strut between the two shoes is actually pushing the shoes apart.

On Duo-Servo brakes, it's really easy. The top of the shoes should be resting on the anchor pin if the brakes aren't applied. If EITHER shoe isn't touching the anchor pin, the park brake is holding them apart; or the hydraulic system won't fully-release pressure.

With the terrible Leading/Trailing shoe design, you'd have to actually look at the park-brake/adjuster strut between the shoes, and the park brake lever coming up from the park brake cable. There should be a gap between the lever and the strut. The shoes will be held apart by the strut--which is also the brake adjuster. But the park brake lever shouldn't be pushing the shoes apart. There is no anchor pin at the top--there's an anchor block at the bottom, but both shoes ALWAYS touch the bottom anchor block. If there's a problem, it'll be at the top.

That’s what I thought. I have the duo servo I believe. 11” I’ll do that as soon as I have it back.

 

[Wickedstick]

Shop claims warped drum (out of round). They replaced drum with warranty drum from oriley. Picked up drove home. Was at 250 degrees. Way better than before. We shall see how it goes.

 

[Wickedstick]

Still getting way to hot. Next step and I argue one I should have done sooner is to get it hot then crack the bleeder and see if drag releases at that wheel.

 

[Frank Enstein]

Find another shop. They blamed the drag on the drum. The drum failure was caused by the drag. I wouldn't let them touch my brakes!

 

[Wickedstick]

Find another shop. They blamed the drag on the drum. The drum failure was caused by the drag. I wouldn't let them touch my brakes!

He tried to say abs module which is possible but there is only one line running from the abs module to the rear axle. Then it splits above the rear diff