So, i finally pulled the trigger and replaced my lower ball joints, tie-rods, and driver side CV axle today. One LBJ was loose, the the CV axle boot was torn and it all felt very sloppy (and the axle made a "clunk" when hitting bumps on turns). I've had a vibration (albeit slight) while driving lately too.

All went well, I went to put the new axle in and it wouldn't slide in.... after removing it again, I found about 3 needles from the needle bearing that came out. That's the one part I didn't have, and couldn't get today, and I had to have it drivable again today, so I put it all together again as is.

That being said. The 4runner drives fine, no more rattling, and no banging of the CV axles anymore, but the vibration is still there, so I assume it's the needle bearing in the side of the differential.

So now, my question.... since it'll be a bit before I can tear into it again, what's the risk in running a bad needle bearing? Mess up the new CV axle?

Any input?

I feel your pain. My second cv swap and reboot last summer had me lose a cap to one of the bearing when packing them with grease. Spent almost an hour fishing through grease with a magnet to recover all the needle bearings.

Id plan on replacing that Cv axle. If you can find the correct needle bearings, and none of the emothers have bent/broken or marred either bearing surface, you might be ok. But if the bearing surfaces are messed up, just swap the cv and save yourself the headache in the future.

Yea, I just hate replacing something just replaced.... but that's the nature of the beast, I guess.

Which needle bearings are you guys talking about?

Where the driver side CV axle connects with the differential.... inside there is a round metal bearing full of little needle rods.

Ok, thanks. Is it the same for passenger side?

I assume yes, but I didn't replace that side, so I've never been into it.

Those needle bearings allow the carrier and the CV axles to spin at different rates when ADD is disengaged. The needle bearings are inside the differential carrier, I'm not sure how hard it would be to change them.

I would think the needle bearings on the passenger side would do the most work, and these are the ones the ADD stub go into. But I'm not sure.

You might want to start shopping for a replacement diff. Not sure if needed but I would probably be worried about the needle bearings being bad.

You don't need a new diff. You just need to replace the needle bearing pack on the drivers side. It's a pretty well known problem with the 7.5 IFS diff. East Coast Gear Supply makes a solid sleave to replace the bearings. It's what is going into my setup when I can afford to re-gear and ARB them.

OP, check ECGS site for removal and install vids and walkthroughs. They also sell the puller tool on the site.

Nice! That is good info!

Thanks, that is good info!