I have a vibration at both rear wheels

Question:

I have this one problem I cannot solve and there is no help from the array of dealers, mechanics and friends I know.

Perhaps the real problem is that few, if any, old-line Mopar mechanics are still around to provide advice.

The problem applies only to the rear wheels. My 1958 Dodge with original linings, drums, hubs and everything else inside the drums has a wheel vibration at both rear wheels. After replacing the drums twice and the hubs once, the problem still exists. Honing was done twice. I installed new after-market drums.

The problem is most notable at slow speeds when the pulsation actually manifests itself at the brake pedal. The car actually shakes at creeping speeds when the brakes are applied.

An old Mopar salvage dealer here hints that the problem erupted in 1958 and that it was universal. Apparently Chrysler attempted to solve the problem by selling only drum/hub combinations that had been mated and calibrated. This is only speculation at this point. Why would my problem manifest itself now?

Everyone here agrees that the problem is non-concentricity between the hub and the drum. As an aside, when the new — and the used — drums were honed, the honing machine worked off of the wheel hole. The actual drum attains concentricity from the lug bolts and not the drum/hub position. The hub diameter is about two inches, and the drum hole is about three inches in diameter.

I have the parts book and the shop manual for this vehicle, and no mention is made in either one about a recall or dealer correction. Can you help me with this problem?

Answer:

Your Mopar salvage yard fellow was right. The hubs and drums on those cars were balanced as a unit, and will cause problems if balanced independently. In 1958 the replacement hub/drum assemblies were sold as balanced units just like the originals, so the only way to remedy your situation is to have a machine shop balance each drum/hub assembly as a unit.

I learned this from my old friend Vince Bunting at C.H. Topping & Co. in Long Beach, California, the oldest and best brake shop in town. They also can get just about any brake part you might need, they do custom machining and they have the books with the original part numbers. You can contact C.H. Topping & Co. at 520 W. Esther St., Long Beach, CA 908131529; chtopping.com; .

I would also inspect the axles to make sure they have not been twisted by hard acceleration or by jumping a curb. And I would check the run out at the drums using a dial indicator and a stand.