New Clutch, slipping sometimes in high gears

Thank you all for your input.
Uodate:
I have finally noticed something that I didnt notice before.

Today ive been driving wb 76/70 through PA. The clutch slips only when im in 13th, amd 11th gears
, 12th and 10th work 100%. I only started noticing this today so it could be coincidental... but every hill I slip in 13th now... even on downgrades!
Im up shifting between 15 and 17 rpms on a dd15. Downshifting between 12 and 13 rpms

 

Yes so apparently there is actually something wrong with the transmission. clutch catches nicely in all top gears on the bottom half of every gear, but slips in the top half of each gear.