Obviously, it's not going to help if you're right below it but the post WW2 tests showed that tanks can survive. The Soviet Union pretty much staked their future on that fact.
Tanks weigh around 40 to 60 tons so their not likely to be thrown about, nor penetrated by flying debris. That thickness or armor is going to slow radiation down too.
Almost all modern tanks have an almost sealed cabin, overpressured with filtered air, as long as folks kkeep the hatches closed. It's for chemical warfare but it works against nuclear dust too. That's also going to help the crew survive the huge overpressure that moves out with the shock wave.
Scroll on down to the neutron bombs for a quick reference.
http://nuclearweaponarchive.org/Nwfaq/Nfaq1.html