Mr Guilfoyle (37) was killed by Shane Fitzpatrick at his home in May 2005, but his body has never been found.
Fitzpatrick (42) of Hapton, was convicted of murder in July 2006 and jailed for life.
But police launched a search of Admiral’s Wood after Fitzpatrick told officers he had buried the body in a shallow grave in the area.
Lancashire Police discovered a body yesterday afternoon but officers said it was too early to confirm whether the remains were that of David Guilfoyle.
The family has been informed of developments and specialist officers are supporting them.