Rear Drums on my 84

[CedarGrove]

So my 84 has a pretty good jiggle in the rear when I'm braking. I've learned to live with it so it doesn't really bother me. I figured it was brake drums. My wife decided that she would get me some new drums/brakes for Christmas to sort out this little problem. We installed the brakes and drums yesterday and the problem was still there. I had the new drums turned today and the problem continues. It's possible that the guy that turned the drums boned it but is there anything else I should be looking out for?

Thanks,

Lewis

[DmaxMaverick]

Bent wheel(s).
Tires out of round.
Tire cord separation.
(all of the above more common than you might think)

Could also be a bent axle. Jack stand the rear end and run it at a slow speed. Any deflection of the hubs could indicate this (also helps to diagnose any of the above).

All this assuming the rest of the brake system is healthy. Isolator valves can cause issues, but not a "jiggle" I'm aware of (usually they lock up one side, or don't work at all).

[CedarGrove]

This thing rolls down the road smooth as silk. Only when I start to brake does it start to jiggle and bounce from the rear. It's similar to warped rotors except that you don't feel it in the wheel or in the pedal. You feel it in the seat.

The wife's 83 doesn't do this so I think I will swap rear wheels with that truck and see if the problem persists. I suppose I could also swap rear drums to eliminate those as well.

Thanks

Lewis

[CedarGrove]

Swapped wheels and tires with other truck and trouble continued. Swapped brake drums from other truck and troubles continued. Now I'm down to the axle and isolator valve.