Studs Cutting Slots in Drums

I have a 1999 Tacoma TRD DLX that I was attempting to pinpoint some bearing noise on this morning. When I took the rear wheels off I discovered that the studs are cutting slots into the drums.

Could this be due to improperly fitted wheels preventing the lug nuts from properly clamping the drum to the hub? The truck, which is new to me, has 16" Toyota rims off another vehicle.

Or could the incorrect drums be installed?

Other ideas for the cause of this wear?

Once I figure out the cause and remedie, I assume it would be ideal to replace the studs, drums (of course) and lug nuts. Anything else?

 

Never have seen “slotted” drums before
But
Think tht is your problem

at the top off each slot, the end of the slot has been wallered out by movement of each wheel stud

get some correct drums

 

Loose bolts looks like it's been doing the for awhile.

 

I haven't ever seen slotted drums before either and assumed it must be wear.

 

How do the shoes look under the drums? I'd probably add new shoes and potentially new brake hardware to your list of items to replace

 

Thats a VERY clear sign of loose lug nuts, also could be a bad hub to wheel interface too.

Toyota wheels are typically hub centric, meaning the hub, not the lug nuts is what centers the wheel together.


Those slots are clearly indicating the wheel was not tight against the drum. It looks like old damage though. New damage would leave bright metal showing.


The clamping force of the lug nuts does most of the work, not the side load on the lug studs.

 

Look closely at any of the slots
One side is larger bc of movement
Other side is perfect curve from machining, also can see dirt/debris
Only making slot larger on one side

agree with Zcolorado
Both wrong drums and loose lugs are contributing to the problem

 

These aren't the wrong drums.

There is no bright metal in the stud slots, this is an old problem.

 

I’m using wrong adjective sorry

Modified Drums?

100% way in the past

 

I'll be replacing the brake shoes and hardware. I have a leaking axle seal on the driver's side and the passenger side pads are heavily glazed.

 

Meaning in the past someone didn't tighten the lug nuts properly? On both rear tires? And this lead to the damage?

So, I should replace the drums and make sure to torque the lug nuts correctly and everything should be fine.

 

Correct on all points here. Except only loose lug nuts on the side with the slots.

 

Just a thought but are you using the correct lug nuts for the wheels? Maybe that is what was preventing the wheel from clamping the drum correctly.

 

Both rear drums show the same slots.

 

I am not sure. Just using the lug nuts that came on the truck. They appear to be lig nuts for hub centered wheels, meaning the nuts themselves do not have a taper to them.

 

those wheels are fine, I bet the PO used the wrong wheels at one point and never got the wheel against the drum. It takes a LONG game to get that much damage. Like you would be listening to loud clanking every time you break for a week.



I believe those alloy wheels need these

 

Those nuts looks pretty much identical to the ones I have currently. I'm beging to think the damage happened and the OP just decided to run the worn drums anyway.

 

Just replace both drums, brake shoes with new hardware tbs. It might be a good idea to get new lug nuts also. JMHO

Who knows when it happened or how just correct it. You just never know what you will run across with a used purchase.

 

If the drum moved that much, the studs/threads in the contact area should be shaved down. Got any pictures of the studs?

 

Good point. It almost seems that driving it long enough to waller out those holes into slots would be enough to break off one or more of the studs