pretty common thing with these machines, the roll pin actually breaks apart eventually and that's what makes it come out, replace with bolt and self locking nut and you never have a problem again, I thinks it's 5/16 x 2" bolt that fits in there, I used a grade 8

Gates

 

WOW!!! thanks a ton I just took mine for a ride today so I figured I better go check them out as soon as I read it. After romving some snow so I could see the front diff. and rear transmission ones have slid out slighty as I didnt check the front transmission but the rear end one has broke off but must still be holding by a little. I guess I know what my job is for tomorrow! I appreaciate the heads up its sure nice to know before it got worse. With my luck I'd be up the frozen river 45 or 50 miles and it would break completely and Id be sitting without rear wheel drive Thanks!!!

 

Would this be the same for the 05 fourhundred Sportsman????