Rear diff leak

Hey everyone, new to the forum and looking to buy my first 3rd gen 4runner.

I found a beautiful 1998 Limited and want to make sure it is in perfect condition as price is quite a bit above average.

The rear differential seems to have a few leaks. From what I've read, this could be caused by a clogged breather, but I’d appreciate any input on whether this might just need a cleaning or if it’s likely the seals need replacing.

Thanks in advance!

 

There aren't any seals on the rear (back side) of rear diff, and that looks to me like it might be coming from the drain plug, and then blowing/wicking up the rear of the diff as you drive at highway speeds.

I'd clean it off well with some brake cleaner and then keep an eye on it. Once clean, it'll be a lot more obvious as to what's going on.

Edit: the other thing that could be going on is that you might have a leak further forward (like from the transfer case), and as oil drops fall from there, they "splatter" back on the rear diff, making it oily in a bunch of spots. This sort of looks like what you've got, so look around up front/middle for leaks as well.

 

Welcome

 

welcome

 

Welcome from Wisconsin!

 

That looks like it’s coming from the fill plug. I’d start by replacing the fill plug gasket.