back end shakes,k1500 1989 silverado 4x4
The last few days going and coming from work,my back end starts shaking violently.If I apply the brakes and slow down it goes away.The speed is about 45 and under and there is no common factors that I can guess,except it scares the crap outta me.When rolling the wheels back and forth while the engine is off and in park,I do not see any problem with my u-joints or driveshaft.The drivers side brake rear has allotta black crap all over the inside of the rim,thats all I can really see wrong.I will be taking it to a mechanic but thought I could get some ideas from this forum,as you all have been polite and helpfull before.thanks for your time.