How do I fix pickles that are too sour? I made dill pickles using an old Ukrainian recipe fermenting the cucumbers in salt water. I wanted to can them when they were finished instead of keeping 10lbs of fermented pickles in my refrigerator. I didn't want to use the salt brine the pickles fermented in,so I made a brine using 1qt white vinegar, 3tbls salt, 1tsp mustard seed,and 1/2 cup sugar. The result is really, really sour pickles! Can I open the jars and dump the brine and use salted water as canning liquid? Or what can I use?
If you are going to do anything, do it when you are ready to put the pickles in the fridge again, not when canning - acid keeps the canned pickles safe. 

So - leave them really sour as canned. When ready to eat a jar, open, dump the brine, add water (whether or not you salt it is up to you and the salt level in the pickles - I'd try plain water) - put it in the fridge. You might want to let that soak for a day or two, and you might want to dump it again and replace it again, depending on how things taste at that point.