Water in rear

I'm working to get my truck ready for the road. I purchased it about 4-5 years ago and it has been sitting..

I am working on the rears putting in new seals breaks cams the whole thing. This morning when I drained the back rear, there must have been at least two quarts of water that came out. The front rear was completely all oil.

There is no metal on the drain plug, the axle splines look good and when I pulled the axles out and the hubs out there was oil. The bearings look okay the races look okay the pinion is tight I don't see anything else wrong except there was water at the bottom of the oil. I did notice there was just a very very small amount of surface rust inside the axle tube and just a little bit on the axle shaft but not at the splines or anywhere near there.

So my question is

1) could that cause me any problem. from this point forth?

2) how did the water get in there? Through the vent?

3) instead of putting the expensive synthetic oil in this rear, should I just put regular gear oil in and run it for a while and then change it and maybe do that a few times to flush it and then put the synthetic in?

4) should the vents themselves be completely changed on both rears or can they be cleaned out?

 

That's excellent advice.

I will thread a fitting into the vent and regulate maybe 10- 15 lbs and see what is happening.

I will post what I find.

 

It looks to me like it would be a button type but I guess I have to take it off to make sure. I'm not sure what the difference in the types are.

It is a 95 Freightliner with Rockwell Rears.

That's good to know about the button type vents to prevent blowing the seals out.

It makes sense that they would get stuck.

 

After @Goodysnap recommended that I check where that water is leaking in, I remembered that I saw a rusty part on the front of the rear.

I can still put air in it to check it, but before I put the seals in and the hubs on, I have to put the cams in. All of my parts are still new in the box if I have to return them. I have another set of rears but I don't know if they take the same cams and seals. I'm trying to avoid buying them twice if I can help it.

So my question is, looking at the picture does that look like water could be coming in there? If so, what kind of damage am I looking at or what kind of work would I have to do to fix that? There have to be bearings and gears that that's running down past.

 

I have to think about if there's a way that I can pressurize it without assembling it. Maybe a plumbing supply would have expandable plugs. I know they use them to test water lines.

Thanks for the advice. I'll post again after I test it.