[markdel16]

This was probably the initial valves which means it was installed in the early 80's.

Anyhow, can anyone assist with identifying this valve stem? For some reason, I think it's a Gerber. The only reason I think that was because I saw a Gerber stem in the catalog at Home Depot which had a 34 stamped on it. This one has a 53 stamped on it. Neither HD or Lowe's had a match.

Also the packing nut is busted off, which is why you don't see that in the picture.

[Caduceus]

The best way to match the manufacturer is by the broach count (number of little notches on the top where the handle attaches.) which looks to be impossible with the condition of the stem and also the length.
Remove the matching stem on the other side of the faucet.
Go back to HD or Lowes and get some help checking the Danco catalogue.
Home Depot or Lowe's will probably NOT have what you need, but once you have the manufacturer and stem size matched you will be heading in the right direction.
I'm a big fan of our local hardware stores. There you may get the 'guy who's good with stems' to match it and possibly have one in stock. Call ahead first to see if they carry replacement stems for most brands and ask if they can help.

[markdel16]

It was a Gerber. Stupid me never thought of checking the faucet handles for a name.

Anyhow, picked up a new stem & bonnet, put it in, and she's leaking more than ever. I'm assuming I need a new seat, which there is probably no way in hell it's coming out of the valve, so it looks like there will be cutting of the wall for a whole new valve assembly.

I put the old one back in just to get the water to mostly stop dripping.

[havasu]

With you going this far, I can't understand why you wouldn't go the extra step and replace the seat as well? At least take a flashlight and take a look to see if you can see a crack or chip on the face of it.

[markdel16]

The reason I didn't mess with the seat yet is because it's very old, and the only way to shut off the water to the shower in question is at the main, which is in a crawl space. I figured I might just get lucky. I will pull the stem back out this weekend and take a look at the seat and take a crack at getting it out and replaced.

[havasu]

Make sure to have a can of PB Blaster (a great penetrate) and a seat removal tool ready!

[markdel16]

OK, she's finally fixed. Just finished up. Well, I didn't put the trim back on yet, but that can wait.

The best advice I found on the internet for getting a seat out was to hammer the wrench in a bit to get a bite on the seat. I thought there was no way it was coming out. It required a bit of oomph, but she came out, and wow was that seat trashed. It got to the breaking point last night, when my last piece of valve stem busted off with the vise grips, and I had absolutely nothing left to grab on that was exposed.

Here's a picture of the aftermath for your amusement (ya think I need a water softener?)

[havasu]

Although I love the pictures of the exploded plumbing parts, most of the sickos here (including myself) like pics of war injuries, so we can laugh and say, "Yep....been there, done that!"

I'm glad you conquered this plumbing problem, and thanks for posting the aftermath.