axle problem

[lsc91]

Well I have an 88 cherokee with vaccum disconnect and just swapped the axle shaft to a full lenght shaft instead of the disco. The shaft came out of a 92 and now it seems that after i tried the 4wd it hasn't come out all the way. While driving at slow speeds i hear a constant thump like its still turning the front drive shaft. Can anyone tell me what it could be? Thanks in advance.

[4.3LXJ]

That is because it is turning the front drive shaft. The disconnect separates one of the axles so that as one axle turns the other turns through the spider gears in the opposite direction inside the axle tube. When that is happening, it doesn't move the front drive line much. Now with a solid axle, it will turn all the time.

[lsc91]

Could a u joint cause the noise that I'm hearing cause my 93 with the same set up doesn't have this issue.

[4.3LXJ]

It could be the drive shaft. Check it for play, rotate it and make sure it is straight.