Cu-Melter

Greetings to All- First post here.
I just landed a 1995 Chevy Silverado Ext Cab 8'box...4x4 w/5.7, 4 speed auto. She's a beaut in every sense inside/out and despite warnings about used 4x4s, I decided to finance the beaut.
I've noticed an earth-shaking event that takes place from the front end at times. This event takes place during idle/crawl speeds only...not highway speeds...and it is sparactic...I cannot tell the readers anything that I'm doing to precipitate this event, but it will most definitely get the user's attention quickly. I just had the brakes redone (calipers/pads/cylinders/shoes) and rotors/drums turning. So I'm afraid the issue could be coming from the front wheel drive whether its engaged or not.
I'm at a total loss here and I'm looking for possibilities that I can point out to the dealer and his mechanic crew for them to troubleshoot before my windows of warranty (14 days) runs out.
Many Many thanks to the responders here.
Ed in 'Bama

2wd-K5

...and what is the event?

Cu-Melter

A violent shaking...literally shaking so hard it vibrates the dashboard...audible feedback. Occurring sporadically (not all the time) at idle/crawl speeds.

2wd-K5

did it begin soon after the brakes were done or before? were the wheels retorqued?

Cu-Melter

Before....The dealer drove it this am and luckily(!) it showed its ugly self. It happens when you apply the brakes at idle/crawl speeds only. So he's gonna replace the rotors up front and see if that will have any effect on the cause. One caliper was already replaced (due to a broken bleed nut)...new pads were installed as well....a 4 foot section of brake line and a wheel cylinder in the left rear drum. Brakes were bled religiously...a whole quart of brake fluid was used in the bleeding process.

2wd-K5

maybe the rotors are warped