The result left them nine points clear of fifth-placed Southampton in the race to finish in the top four of the Premier League.
Van Gaal was delighted to give fans the win following a rough patch earlier in the campaign.
Speaking about the game, van Gaal said: ”I was very pleased because the fans are pleased and we are playing for them. The fans have not always had a good time because started very bad. But still they were supporting, and now the results are coming back. It’s great to be a supporter of Man United right now.
“That is the most pleasant memory – you have seen the arousal of the fans. I cannot complain about the fighting spirit of my team because the first 15 minutes Manchester City dominated and scored. We equalised and regained confidence and then from there we played a fantastic match. Of course I think maybe we could have started this form earlier but the last 20 matches we’ve been good and better than most of the Premier League.”
Aside from a poor opening period, United were excellent against City and thoroughly deserved their resounding win.
Van Gaal has well and truly brought the good times back to Old Trafford following the disastrous reign of David Moyes last season. Now back where they belong, United are looking up in the table and will have a win against Chelsea firmly in their sights as they look to build momentum ahead of next season.