Ok two things to look for. First one is if you got your trans new the plug that they put on the out put shaft may be pushed in there. I have seen them come with no end on them its like a rubber spine sleeve that can get pushed in and not seen easily. Second thing is there are two types of yokes one comes with a hole in it to let air out as it goes in and out, if the out put shaft has a o ring on it and if your using the one with out the hole and the o ring out put shaft it will not go in all the way and if it don't have the o ring it has to have the yoke with no hole in the end.
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