Re: Re-installing rear brake drums

Posted by TxGoat On 2023/7/27 7:19:27

It looks to me like your brake drum is slightly too far inboard when mounted and tightened. That could be due to the fit of the hub to the axle taper or to the location of the axle shaft.

I assume the axle shaft is located by the wheel bearing.

Is there any chance that the wheel bearing is either off-spec or not seated properly in the axle housing?

Is there any chance that the location of the inner wheel bearing race is not properly located or seated on the axle shaft?

A bent axle or other run-out situation might or might not cause vibration to be felt in the car, and it would probably do so at some particular speed range, if it did it at all. That kind of interference might cause an intermittent grinding sound instead of a steady grinding sound.


An incorrect fit between the axle taper and the hub is a fairly common problem on older vehicles or vehicles that have had parts replaced.

If the hub, for any reason, goes too far onto the axle when properly tightened and seated, it could cause your issue.

The hub or axle taper, or both, or some issue with the key or keyway can cause problems.

Swapping brake drum/hubs left for right might improve the situation.

Otherwise, if everything works well except for the slight brake shoe to drum face interference, I'd consider carefully grinding off about 1/32" or a little more from the outer edge of the brake shoes.

I'd do it with the shoes mounted.

A 4" right angle grinder might be handy for this.


DON'T BREATHE THE DUST!

I'd want to do this outdoors and I'd want to clean up all grinding dust before reassembling the brake.

Keep the grinder contact with the shoe moving to avoid heat buildup, and keep the grinder wheel contact moving along the edge of the shoe, not across it, for a better finish.

IF the drum can be removed from the hub,
it might be possible to make a shim to space the drum a little farther outboard.

I'd want to keep the shim thickness to a minimum, and it ought to be made from metal. A steel shim or two made from flat sheet metal ought to work.

A Dremel tool could be used to clean up edges and lug bolt holes so that the shim would lay flat. The shim ought to cover the entire contact face between the drum and hub.