the nut that holds the bearings and drum on for my front left wheel keeps working its way loose after about a week or so of driving. this makes a howling noise that always goes away after it is retightened. is there a way to keep this from happening? has anyone else had this problem? maybe wrap the threads with teflon tape? thanks guys

Teflon tape isn't a threadlocker, so that won't work.

Is the stamped sheetmetal retainer (looks like an old-fashioned, non-twist-off Coke bottle cap with a crown on it) missing? How about the cotter pin? Both of these items have to be there or the nut can unscrew itself.

But if the retainer and the cotter pin are both present and you keep having to remove the pin and retainer, tighten the nut, then reinstall the retainer and pin, you have a different problem: Your bearing races are wallowing out their lands in the hub, causing the assembly to grind itself looser and looser. In that case, you're not tightening the nut because the nut has backed off, but because extra slack has been created in the assembly with the nut standing still.

thats interesting. ill have to check on that. thanks.