Swapping front end gears, now lots of slop between ring and pinion

I have a 1984 d50 and I picked up front and rear end gears out of an 87 raider at the junk yard. I just put the pinion and carrier back in. And there seems to be quite a bit of sop between the ring and the pinion. I pulled everything back out to make sure I wasn't missing any pieces it that I had installed the wrong pinion or something and it all looks good. Anyone ever don't the front end gear swap from 3.9 to 4.625 and experienced this? Was there any changes between 84 and 87 that i am not aware of? Thanks

Pretty sure you need to set the backlash. There's a thread on the site somewhere, I think a LSD thread with the info.

This had occurred to me too but I don't see any adjustment for the backlash. Also all I find for adjustment is for the rear differential.

There is no adjustment I see. I just measured the ring gear thickness and my 3.9 gear is 3.5mm thicker than my 4.625 gear. Looks like I'll try and shim the ring gear with some grade 8 washers and see how that works out.

when you got the gears, did you just get the gears and not the carriers and snouts? that may be why they are off - the 4.625 carriers may be different or the snout may be over enough to allow for the thickness difference.

I just got the ring and pinion by themselves because the junkyard local to me charges out the ass for the whole thing. I think it will work alright with some spacers. I'll test fit it soon