I have a pull-up diverter valve stuck on a bathtub faucet. It's stuck up so we can only take showeres, and wed' like to be able to take baths as well. Is this a case of just needing Wd40, or are replacement parts needed? This has happened before, and when it gets stuck, it's completely stuck. It won't move at all.

I have never had one stick like you have described. Since my secoiond suggestion will be to replace the spout completely you can try my first suggestion. Hold a chunk of 2x4 or 4x4 under the spout and give the diverter a smart smack with a soft faced mallet. If it doesn't work and you shatter the stem we can help you replace the spout with a new diverter.

We've tried the method of hitting with something solid, and it hasn't even come close to working. The valve is really jammed in. A problem in the equation is that we have a lazy, inattentive landlord. I'd like to be able to fix it without having to replace the parts. Apparently the landlord fixed it once with a pair of plyers, but I wasn't here to see it. The valve is the standard metal rod, attached to a piece of hard pastic inside the valve. Do you think it would work to spray with Wd40 and pull it from underneath with plyers? I would really nice like to have to replace this.

Maybe you aren't hitting it hard enough or supporting it from below with a block. You should be able to almost drive the rod right out the bottom. You may try the other approach and tell your landlord it must be repaired at his expense or you may look into plutting some of his rent money into an escroe accout until the matter is settled by the legal authorities who govern housing. It might tick him off and I understand if you don't want to go there but it is his responsiblilty.