Eaton Fuller 13 spd making noise

So in March of last year my 13 spd took a dump on me and I had it replaced with a remanned 13 spd. Now I am getting noise when I'm in high range and I split up, especially in what I guess would be 11th gear (all the way right and forward in Hi transfer and split up). I've called the shop to talk to the guy who put in the reman and he got the information and said he would check his manuals and call me back, have yet to hear from him. I crawled under the truck and checked the oil in the trans and it was about 1/2 gallon low so I filled it up. I'll be driving the truck again tomorrow so I'll know then if that fixes it but I was wondering if maybe there was someone here who knows what it could be with this description? I really don't want to be faced with another transmission bill but I want to get this nipped in the bud. Thanks in advance.

 

Mostly under a pull. Rear end is newly rebuilt and this problem was going on before and after it was rebuilt as well.

 

It's only when I'm splitting up but I have noticed that shifting seems to be getting a little more tough in all gears now.

 

Tranny temp has never been over about 140