Well I just replaced the u joints on my 2015 Ace with 998 miles on it. The back one was a total rust bucket and the front had a tad of grease in it. Why would they put a u joint in a ATV and not have a zirk fitting on it? It was not that hard to get out, I did not remove the gas tank as it will come out with lots of love and a few cut to your hands. I got my u joint from All Balls and the roll pin that came with the joint will not fit the hole unless you beat the heck out of it to get it in. I reused the old one as I did not want to beat the [email protected]#t out of the front diff shaft. Now it is time to go get some mud on it up here in the great northwest.