Rear brakes

[mblab]

Hi
New here. Hopefully someone here can help diagnose an issue.
1997 GMC K2500 short bed extended cab. 208,000 miles, owned since 2001 / 21,000 miles. I've had a pulsating brake for several years, last year, redid the front with new Wagner pads and rotors. Didn't solve the pulsing. Last week, installed new rear drums, hoping that was the issue. Lots of life left on the shoes, so didn't change them. Now, when the brakes heat up (lots of steep hills in western NC) the rear doesn't pulse, it HAMMERS. What have I done? Did I adjust the shoes too tight? Did I install the shoes backwards? I'm going to go back into the rears today to have another look.
Any help is welcome
Thanks, Mike

[leolkfrm]

Welcome to the forum
first do you feel the pulse in the steering wheel or the seat?
What type of brake material did you use? some vehicles don't like metallic shoes
Did you flush the old brake fluid out of the lines? after time the fluid gets like molasses and does not flow as well, worse in colder weather

[mblab]

Thanks, Leo
Pulsing is not thru steering wheel. Definitely thru the seat. Like I said, I changed the drums(new) but not the shoes. And no, I didn't flush the fluid. Weather here has been warmish recently, and I didn't experience any trouble when it was +6F 2 weeks ago.
Mike

[wild bill]

i assume then that you are feeling it in the brake system .the only thing i can think of is the drums and the new rotors are out of round . did you have them turned ? if so you might have you abs brake's checked out .