Before you go to the trouble of removing them, measure the thickness to make sure there is enough left to have them turned. The process removes a certain amount of metal, and there is a minimum specification. If they are thinner than this they can't dissipate heat properly and are even more prone to warpage and uneven wear.

Use a micrometer, and if you measure at several different points you may be able to detect uneven thickness---it won't be much---a couple thousandths of an inch could be enough to give trouble. There is a spec for that too.

Runout can be checked too. This is side-to side wobble. Assuming the wheel bearings are properly adjusted, it should be minimal. For this measurement you will need a dial indicator and a suitable stand. You may be able to borrow or rent them---they aren't cheap, nor are they useful for much else. The micrometer, on the other hand, has lots of uses and can be found for $30 or so for a new Chinese one, or even less if you get lucky and score a good old American made one at a yard sale. (I have one I paid 50c for--the seller had no idea what it was)