Here is all that I have, taken from Beauchamp's "Revolutionary Soldiers Resident or Dying in Onondaga County, N.Y."
Page 105, Town of Manlius,
"In / memory of / William WARD / who died 7th Sept. / 1795 / Aged 49 years / In memory of / Susanna / consort of Wm. WARD, / who departed this li / fe Sept. 2, 1819 / aged 66 years & 8 months. /
Manlius Cemetery. This pioneer settled on Lot 97 (Military Tract #) in the spring of 1793, and was sole proprietor of that lot in '94. That year he was made Justice of the Peace. In the present town he built the first grist mill. In Conn. rolls his name appears in Capt. J.R. MEIGS' Co., '75; as corporal in Capt. THROOP's Co., Conn. Line, '77-'79, and in Col. SWIFT's Levies, 1780. Probable. Susanna, an administrator, Dec. 3, 1795."
Note: from the above you may assume that there was a gravestone in existence c1880's-1912 when Rev. Beuchamp was compiling this book. He surveyed all of the known cemeteries in Onondaga Co. at that time recording earlier stones. The "Probable" means that Dr. B. suspected that the Rev. War service recorded did in fact apply to this veteran. I would check the DAR Index to see if anyone else has joined under him and send for the file if so. You are not likely to find much in his estate file because from my experience the wills testate and intestate files recorded in Onondaga Co. for that early period of time are extremely terse. The note that his wife was administrator is likely all that you would learn from that file, however if you are in the area then you should check it anyway at the Surrogate's office.
For further clues, write to The Onondaga Historical Association, sending a donation usually helps, and you might try Barbara Rivette, she is or was the Town of Manlius Historian and a very capable and active historian.
That is all that I can help you with. Good luck.