i got both types just to make sure that i didn't have the wrong type, i have the rear axle that has the smooth seal not the one with the lip, and the smooth seal fits easily in the spot. but it also comes out too easy, like its too small did they make a bigger type that you have to seat in, and won't come out so easily. when i say easy i mean when i put the c pin in the axle pushed it back the seal came out. any presure pushes the seal out of place i hope i don't need a new axle housing. thank you in advance for any help you give

 

Depending on what axle you have, there are different size seals. The replacement seal may look different than the original. It should not fall out like you described. The replacement seal might have a lip, or shoulder on it. Either use a seal installer, (best option) or a block of wood, and drive the seal inward until it is flush with the axle housing, or the shoulder stops against the axle housing.