Front Drive Shaft/FlexDisc Removed. Next Step?

[SeanIngstrum]

Okay, after going through all 7 gates of Hell and finding the 8th, the front drive shaft/shaft plate and flex disc are removed. No damage visible to the transfer case or shaft itself. The problem seems to be at the flange where the flex disc bolts to the differential. The flange is very loose. There is tons of play. It is obviously not connected to anything inside. I can spin it, push it up and down and side to side and all directions in between. I would of taken a picture but there is nothing really to see. I did see a nut in the middle of the flange so I took it off hoping I could pull that gear out of the diff (I really don't know what I'm doing at this point in my journey) but it just wouldn't come out. Pic of the nut included. I'm guessing it's held in internally? Anyways.....Worst news, I need a new front diff? I know you can buy new bearing kits for these diffs but do they need to be pressed? Are they magnetically fitted? I know that I will need to determine if mine is cast iron or steel, which I think mine is iron. Thanks for any help! I know I'll need it!!

[jdstrickland]

If you can turn the flange where the shaft bolts to the diff, and the axles do not turn at about 1/4 to 1/3 the rate, then you have a dead differential.

The flange (input shaft) of the diff has the pinion gear on the inside of the diff. The pinion mates to the ring gear, which houses the carrier that the axles fit into. I'm not sure of the gear ratios in the X5, but a typical ratio would be something like 3.45:1 or 4.11:1, which gives you 3.5 or 4 revolutions of the pinion shaft for one rotation of the axle shaft(s). The pinion shaft should have no play in it at all, either moving linearly in and out, or rotationally -- slop in the gears.

[SeanIngstrum]

Originally Posted by jdstrickland

If you can turn the flange where the shaft bolts to the diff, and the axles do not turn at about 1/4 to 1/3 the rate, then you have a dead differential.

The flange (input shaft) of the diff has the pinion gear on the inside of the diff. The pinion mates to the ring gear, which houses the carrier that the axles fit into. I'm not sure of the gear ratios in the X5, but a typical ratio would be something like 3.45:1 or 4.11:1, which gives you 3.5 or 4 revolutions of the pinion shaft for one rotation of the axle shaft(s). The pinion shaft should have no play in it at all, either moving linearly in and out, or rotationally -- slop in the gears.

Should you be able to "feel" if there is fluid in the differential? When I was messing with it, it sounded and felt as if there was no fluid in the differential what so ever. Just felt like metal on metal. Would it feel smooth if there where fluid in it? I'm guessing that is why mine went bad. I guess since it is bad (most definitely) I can just pull the drain plug to find out for sure.

[SeanIngstrum]

Originally Posted by jdstrickland

If you can turn the flange where the shaft bolts to the diff, and the axles do not turn at about 1/4 to 1/3 the rate, then you have a dead differential.

The flange (input shaft) of the diff has the pinion gear on the inside of the diff. The pinion mates to the ring gear, which houses the carrier that the axles fit into. I'm not sure of the gear ratios in the X5, but a typical ratio would be something like 3.45:1 or 4.11:1, which gives you 3.5 or 4 revolutions of the pinion shaft for one rotation of the axle shaft(s). The pinion shaft should have no play in it at all, either moving linearly in and out, or rotationally -- slop in the gears.

Also, thank you for the feedback. I pretty much knew the bad news. Just needed to hear it from someone else. HaHa

[X53Jay4.8is]

Originally Posted by SeanIngstrum

Should you be able to "feel" if there is fluid in the differential? When I was messing with it, it sounded and felt as if there was no fluid in the differential what so ever. Just felt like metal on metal. Would it feel smooth if there where fluid in it? I'm guessing that is why mine went bad. I guess since it is bad (most definitely) I can just pull the drain plug to find out for sure.

Just pull the drain plug for the front diff and see what comes out. Old oil and metal debris if its toast. Getting a front diff a rebuilt one is not too difficult. Its just out with the old and in with the new.

[SeanIngstrum]

Originally Posted by X53Jay4.8is

Just pull the drain plug for the front diff and see what comes out. Old oil and metal debris if its toast. Getting a front diff a rebuilt one is not too difficult. Its just out with the old and in with the new.

Ok, definitely best it sounds like. Thanks so much for your advice! Much appreciation!