I pronounced "Erudite" with a long "U" sound, but I watched about five videos on how to pronounce the word, and all seem to be a short U. In fact, most sounded like a short "A" sound which makes little sense to me.
In this regard, I notice that many of the short vowel sounds pronounced in English don't seem that distinct from each other, at least in the United States. Maybe this is why so many speakers from the British Empire use long vowel sounds, just the opposite of American speakers. For example, "Evolution" with a long E sound.