Any point neutering a 3 yr old dog?

[TroublesomeTownHouse]

3 year old lab has suddenly started to run off and chase other dogs. He's also got a bit growly occasionally with other young males.

He's shown interest in bitches in season before but not enough to bother having him done.

Suddenly he's started running off (sometimes a very long way) after a dog he wants to play with or just likes the look of. Last time the bitch had been done so certainly not in season. It comes out of no where and is very stressful as he's run across a road before and obviously he's very much faster than me!

Might the chop help in any way or is it too late? There are opposing views and I can't decide if it'll be a waste of time as I know there are health advantages to leaving the tackle intact.

I had the implant put in my dog yesterday - mostly to see whether it will give him an easier life in terms of other intact dogs having a go at him. Could also do without the humping.. interesting to read about weight gain and other issues though - I went for this as it's a way of seeing what impact castration would have without having to go through it initially. Dog is large and had a GA a few months ago for another op - didn't suit him at all and was very expensive.. He's 2. Am looking forward to seeing whether this works as we've had some crap situatons with other male dogs lately.

Well ... After talking to the vet , three times I went ahead and had my boys neutered ... the health benefits kind of swung me.
Since ( a week and a half on ) my nervous one has been a bit more barky on the lead towards other dogs , the shorter boy has gone the other way and doesn't really care. They are both as cuddly at home as always but when they are play fighting the taller one hasn't so far taken it too far like he used to occasionally so cross fingers ... I'm thinking reactivity will be a ongoing work in progress with him on the lead
But aside from having to wear the surgery shirts as they both keep licking their wound .. touch wood they seem happy and not looking for their Crown Jewels