Probably a dumb question, but hoping for a sanity check before I proceed.

I replaced the rear diff because it was leaking at the rear passenger CV axle in a new-to-me LR3. It also had a crazy loud bearing noise on throttle and when coasting in gear but in neutral the noise when away. The new diff was a junkyard replacement but it's rust "petina" indicated that it didn't have a leak before i installed it. After replacement the noise went away completely. Fast forward to today...

There is a leak at the CV axle input on the same side that was leaking before the diff replacement. Am I right to assume that the CV axle is probably leaking because it was damaged from riding on bad bearings in the old diff for so long? Does that make any sense? I'm game for replacing it but hoping someone might doublecheck my logic here before i throw parts at it.

 

Did you replace the output seals before installing? They are soooo easy to do and so cheap. What can cause them to leak is improper install of the CVs, the output seals must be protected, or as you suggest it could be shaft wear. But then I would expect leaking to have started sooner than later. My guess is damaged/worn output seal.

 

Stupidly enough I didn't replace the seals before installing, that would have been clever. The diff has only been in for a few weeks, and it mostly sits in the driveway right now so it started leaking pretty quick. Either way I guess I'm taking the CVs out to have a closer look. Thanks!

 

New seals are recommended even when installing a new shaft. I would just get one or two new seals. Make sure they have the red protector! If they dont ship with one, they are junk. You need for install. Which means the protector mostly stays in place until the shaft is inserted a bit. Then you break the plastic in half which lets the protector come out, then a final push to get the shaft in. I learned this the hard way when new seal leaked, the seller (Lucky 8) did not ship with with the required protector so I went and installed anyway and it leaked. Got another seal with red protector, no issues with install and never leaked again.

 

Think i’ve got a similar issue. Where did you find the seals that include the red protector?

 

Just look on eBay and such, most will show what you actually get in photos. I dont recall the part number for rears, but you generally will find these types of seals are used on lots of platforms. For example, the front seals are BMW part 33107505601. Knowing that you can find more sources and cheaper prices. I tend to go with Corteco brand seals. You will have to figure out the rear seals part number and go from there.