It will quite likely but most certainly not immediately (as he's still entire and already 2 years old). It will take weeks if not months for his behavior to chance and the hormones to settle (if at all).
It's best to discuss this with your vet, but I would also suggest obedience training classes on a regular basis for such a big dog. Large dogs really tend to enjoy such classes and I think stronger bonds form & respect for their owner. And you're not too young either, as I took my Doberman from the age of 10.
Anyway, back to neutering.
If he is not a stud dog, there is no reason whatsoever to keep him entire (un-neutered). It's highly advisable to neuter him as this would prevent him from developing prostate cancer - very often found in male dogs (often too late).
Taken from
this website:
"Dogs are the only non-human species which also get any significant amount of prostate cancer. One in every 150 male dogs over the age of 8 was found to have prostate cancer. Unlike human disease, canine prostate cancer is an aggressive disease that spreads rapidly to lymph nodes, lungs, and bone. Usually, when dogs are diagnosed with prostate cancer, it is in its advanced stages. There were no data in the article describing the rates of prostate cancer in neutered versus intact dogs."
And
here is a further great little website with reasons why to spay / neuter your dog.