MTFCA Forum

Is there any symptoms that would show up before the thrust washers go bad? Or do they just crumble and you’re coasting? I thought last time I had mine out that the left rear hub was warm. Could be parking brake. We’re going to be moving soon, 15 miles away, and I’m wondering about driving it or finding someone to trailer it.

They tend go suddenly. You don't necessarily just "coast" when they go. But, they do make a horrible noise and should never be driven any farther. I have to believe a 15 mile drive should be okay, assuming you've driven the car a bit already with no known issues.

If you decide to trailer, let me know I can buzz over and help you move it

Likely the parking brake is a bit tight. That would heat the drum if it is dragging. Try driving on a level surface such as a vacant parking lot at a slow speed. Then pull on the parking brake. If the car pulls to one side, that side is tighter than the other and they need to be equalized by lengthing the rod on the side that is pulling or tightening the opposite side. They should not drag at all with the brake handle forward.
Norm

The thrust washers are on either side of the differential. Heat on the outer left is not related. Parking brake or a really really bad outer bearing. They do go suddenly allowing the axle assembly to move sideways. They do wear over time, but they get looser. No heating. The left one in particularly fails with noticeable symptoms. The gear mesh opens wide & gets noisy. The right side can get noisy from the assembly shifting left & grinding the wheel nuts on the brake shoes & perch nut.

My experience mimics Steve's

The only time it has ever happened to me was when I was driving another owner's car after rebuilding the front axle assembly. The ring and pinion gear mesh allowed the gear teeth to skip over each other, making a dreadful din. It let go suddenly as I was braking to make a U turn to go back to the garage.

Allan from down under.

If you still have babbitt thrust washers I've been told that the differential oil will sometimes show some gray material if you spread a little out on some white plastic or similar material. Likewise, shiny gold specs could indicate bronze bushings. Regardless, if you don't know, you need to find out.