I just don't care for the taste or consistency of low cal/low fat/canola/fat free or whatever mayos. To satisfy mayo cravings, I have two suggestions:
Take out the Mayo when making Tuna Salad. I simply add a can of tuna, mustard, and pickle relish. There's a ton of flavor without all those extra calories. Instead of bread I grab some Romaine Lettuce leaves and spread my tuna mix over it. It's delicious.
Instead of using 2 tbsp of Mayo on your sandwich, try smash and spread or slice 1/4 of an avocado on the bread. You'll save 36 calories and 6.6 grams of fat. Plus, of the fat that you do get from the Avocado, 4.2 grams are belly flattening MUFAs, not to mention all the other health benefits.