Oil coming out of breather on rear differential on 579

I have a 579 thats 2.5 years old.

This summer has been super hot lately..110-112 degrees lately.

I've been getting oil come out of the breather tube on the rear differential pulling over the grapevine.

It's not a huge amount of oil but it's making me mess and it's annoying.

I took the plug out in the morning before I took off and it was coming out and it appears to be over full.

This just started this summer so I thought it was weird.

It's synthetic oil and it appeared and smelled normal. It has 300k on it.

Any suggestions guys?

Thank you!

 

OK I'll check all of those things.

Thanks everyone!

 

It got up to 300 degrees today....the rear differential...going over Donner Summit and that was really disturbing. I I was maxed out at 80k.

I've had some of my fellow drivers say it's good to 300 and even Peterbilt said the same thing.

When I'm not in the mountains it's fine.

I have to get the tractor serviced really soon so hopefully it'll get figured out.

I'll only have this tractor for another 8 months and then I'm trading it in for a new one. I'd like to not blow a rear between now and then.

It seemed like it stopped blowing oil out of the breather tube though. When I pulled the plug the other day, it seemed over full.

Thank you for your replies everyone!

 

Had it looked at today. Oil is good and no metal. Apparently the rear driver was over full and it seems that the gauges are wrong.

I'll have to get one of those fancy IR heat guns.

Bizzare stuff.

They are under warranty for 500K miles too so that helps I suppose.

Thanks guys. The saga continues!