Brake question, 86 Suburban

[dagna]

I recently bought an 86 Suburban with the heavy duty trailering/towing packages. When
I got it, the rear brakes grabbed, and seemed tight as well. I replaced the shoes and the
leaking wheel cylinder. After that, the brakes felt "normal". That is, the pedal went
about mid-way, and did not grab, or seemed very sensitive. Now, after awhile, they've
tightened up again. It is real easy to lock them up. These are 13"x2.5" drums. I wonder
if this is normal for an 8000lb GVWR Suburban that is not loaded.

Thanks.
Dave

[GMMerlin]

Check the rear brakes again...you may have fluid on the shoes

[dagna]

Originally Posted by GMMerlin

Check the rear brakes again...you may have fluid on the shoes

Nope, they're dry. They aren't grabby like brakes wet with fluid. They're just tight.
I backed a Kenworth tractor out of our shop the other day. The brakes on it were
just as tight.

[Firminator]

Dave, If you haven't already tried re-adjusting the rear brakes after a break-in period you might want to. If you did the work of replacing the shoes yourself, you know that there is an adjusting screw that has what looks like gear teeth on it that allow you to adjust the amount of pressure the pads put on the drums. Some of the 70's Chevy trucks have rear brakes that can be "self adjusted" by briskly applying the brakes while moving in reverse, but I don't think our 86's do that.
Here's something else to think about but I don't know if it will help because my 86 doesn't have a trailer package. In my almost 18 years of driving it, the front disc brakes have always carried most of the braking load. The rear brakes have never felt tight. Perhaps your front disc brakes aren't performing properly and need attention?
One last theory. It's only a theory. I'm no expert, so I don't really know, but it's might be something worth investigating. If there is a component in the braking system that distributes pressure between the front and rear and if it is not functioning properly so that it is either applying too much pressure to the rear brakes or not enough to the front brakes, then your rear brakes would feel tight and easily lock up.
If you plan on keeping your 86 Suburban, please send an e-mail to me so we can compare notes and share resources.

[dirty dan]

Just a thought... You recently bought the burb. Are your rear shoe adjusting screws on correctly?? If they are turned around, sometimes the adjuster arm can still reach the star wheel.
Normally on the self adjusting setup, you won't get much adjustment on the rear wheels unless you slam on your brakes while in reverse. The porportioning valve doesn't let enough brake fluid to the rear cylinders on normal braking.