Trays 6 & 7 are the HCF's and should be able to handle that weight.
Do you have other paper that weight range and does it jam?
When it jams does the paper look damaged?
Does it multi-feed?
Whats the fault code you are getting?
Does it jam one sided?
Thank you for using the forum.
I have checked the paper specs for this model http://www.support.xerox.com/support/770_DCP/support/en_US.html?objGUID=1024 and it identifies the trays max paper weights is 80#. For anything higher you need to use the bypass tray.
Tray 1-3 - 550 sheets each, 64 - 220 g/m2 (18 lb bond to 80 lb cover) uncoated; 106 - 220 g/m2 (28 lb bond to 80 lb cover) coated
ByPass Tray - 250 sheets, 64 - 300 g/m2 (18 lb bond-110 lb cover) uncoated; 106 - 300 g/m2 (28 lb bond-110 lb cover) coated.
I hope this helps you. If it doesn't I would recommend that you contact phone support at 1-800-821-2797 for assistance.
I cannot get this media to print from either tray 6 or 7. Jams in all areas. Have ried everything I can think of. Either jams in the drawer - first unit - main unit and third unit. Wasting a lot of this special ordered paper. Needs to print 2-sided for one job and one sided for another job. Specs for paper:
18 × 12 in. GS
17.5 Pt. Caliper