Do you have a diagram or schematic of the diverter stem for a three-handle shower?
I removed the diverter stem OK, but I can't figure out which piece needs replacement.

What kind/brand/type of faucet do you have ?

Generally, diverter has black washer, plastic ring, and seat that may be cause of leak, We ALWAYS replace all three regardless of the condition of the other two.

Do you have a diagram or schematic of the diverter stem for a three-handle shower?
I removed the diverter stem OK, but I can't figure out which piece needs replacement.

Here you go! Good luck, Tom

If you have leak or the divertor is not working properly replace the washers at the end of the stems, see the image below, good luck.

John