Hey all,
I have a fairly detailed question due to how everything worked out;
I am trying to find the source of noise on a 77 280z with an R200 dif. For sure there was bearing noise so I replaced them and since I was there, I pulled the dif to check it which seemed fine on the indicator.
First off EVERY bolt was loose in the entire drivetrain. Second, my son noticed from the previous owners facebook, that the car was flipped on its side to weld in new rails and pans. I found that the axle on the drivers side won't go back into place when putting everything back together. I can't remember if I had to pry it out but I do remember that side had a lot of noise when isolating that wheel and I also noticed a lot of wear on the companion flange where it hits the grease seal and the outer bearing was loose on the stub. I am measuring about a half inch difference from the side flange on the dif to the companion flange in the hub. I swapped the axles and they are the same.
First question;
Is it true that the R200 is a different size on each side and Datsun just used the play in the axle with same sized axles?
Do you think that flipping the car may have wonked the hub enough to now make the axle not fit?
I am suspicious of the loose bolts that may have been done to lessen the noise of the drivers axle being jammed into the dif.
Is there something I may have done to make that side not fit like tightened something first before letting the differential find its spot or are there any adjustments for lateral differential positioning?
I'm pretty sure the differential is sitting where it wants to and I don't want to shorten an axle before I ask someone.
It seems to be maybe a sixteenth to an eight inch short of fitting properly.

I am guessing from the sound of things you have a cv swap? Which cv conversion are you running? Which adapter companion flanges are you using? The S30 is narrower than the S130 and Z31 so any cv conversion is TIGHT! All the adapter companion flanges are very long as necessitated by the length of the stub axle. The acr drawn by the lca makes installation far easier at right height and can be nearly impossible with any droop. Have the tulips been flipped? This is a necessary step when using Z31 cv's, I assume you could also flip the tulip on an s130 cv conversion but I don't think it's generally required as the z31 conversion is. The cv's are equal length but some swear the oe's were a touch different, It's not uncommon for one side to be tighter than the other due to the offset of the diff housing. Rolling the car on it's side should have no effect especially if it was done on a rotisserie. You can run adjustable lcs's to kick the bottom out a bit but this will add camber and you'd need camber plates to correct and then you would have moved the entire wheel out.

No it's not a swap. It's an s30 with an R200 all stock, so no camber adjustments. I should have mentioned this since I did read about problems with the swaps. I remember seeing the car on its side with nothing special in the way of hardware to help the procedure. The wheels may have taken the lateral weight but I really don't know for sure.

Oh, you still have the U jointed half shafts and have difficulty fitting them in!? They are telescopic and shouldn't not have any trouble fitting in, You might need to replace your halfshaft,it should have a bit of telescopic movement. Also pretty unusual for someone to roll one of these cars over on it's side without removing the suspension. Look At the vertical members on either side of the diff, these locate the lower tie bar as well as the rear mounts for the lca's, They should be perfectly straight up and down. Check the mustache bar, make sure it's not bent or slotted or something weird. The stub axle can't go too far into the strut housing unless someone took the bearing races out. The companion flange should be only about 2" thick and flush against the back side of the strut housing. Some pictures might make ti easier to spot anything odd.

Well I got it.
I took another look at it tonight and loosened the dif tightened the flange on the dif side and the axle was still an interference from the top. I tried it from the bottom and it went right in with about an eighth inch of play. That seems low since the other side has a full 5/8 to 3/4 or so to play with.
It's possible that the passenger side axle had just a bit more travel maybe...
or it's possible that moving the dif had something to do with it but unlikely since the holes seemed to have normal clearance...
or I never even tried loading it from the bottom, probably.
Anyway, it's installed and I'm tired.
Thanks for the help. This would undoubtedly be sitting for a week without it.