I love Claydol, but he has an enormous amount of weaknesses. He's mainly used for walling Fighting and Rock attacks (along with an immunity to Electric and Ground), so make sure that's his main purpose on your team.
Oh, and by the way, if you're worried about fatally Ice Beaming things like Salamence and Garchomp, stick those 136 Attack EVs into Special Attack.
A few noteworthy mentions:
Claydol survives Ice Punch from Electivire by roughly 50%. And since he either resists or is immune to his other attacks, Claydol can easily switch in on 'Vire unless your opponent goes prediction crazy. And an Earthquake from him (with the EVs in Attack) will usually always OHKO a standard Electivire.
An Earthquake from Claydol is about a 2KO on a standard Tyranitar. CB Tyranitar is everywhere these days, and Crunch from him will do MASSIVE damage to Claydol. Possibly not OHKO it, but pretty damn close. So be sure to play him carefully when attempting to take down TTar.
That said, Claydol is bulky, but not too bulky. Meteor Mash is a 2KO on Claydol, so it goes to prove that his primary role in a team is walling Fighting and Rock. I hate to stress that, but otherwise your Claydol may let you down. Very few things will completely OHKO him, but his offensive power doesn't quite make up for it. And with so many weaknesses, you've got to know what you're doing to play him well.
Just my 2cents!