Gilder stands at 6-under-par, tied with Bruce Fleisher, Dana Quigley, Dave Stockton and Jose Maria Canizares. All five men opened in 65.
Gilder is in search of his second win in as many starts. The 50-year-old 'rookie' won the Verizon Classic two weeks ago. Friday in Newport Beach, Calif., Gilder followed up an even-par front nine with a 6-under-par 30 on the inward half.
Fleisher is in search of his first victory in 12 starts. The 1999 Senior PGA Tour Player of the Year won four times in 2000, none of which came over his final nine events. This year, Fleisher has recorded a pair of top-3s in three starts.
Quigley came close to winning earlier this year in the ACE Group Classic, where he finished runner-up. He is trying to follow in the footsteps of fellow iron-man Mike McCullough, who captured his first Senior victory in last week's Mexico Senior Classic.
McCullough holds the record for most consecutive Senior starts in which he's been eligible - 152 and counting. This is Quigley's 135th straight start in which he's been eligible, and his 121st overall.
Stockton hasn't stepped into the winner's circle since the 1997 Franklin Quest Championship - 89 starts ago.
Still, that's better than Jose Maria Canizares, who has yet to win in 108 career events. Canizares led after the first round of this year's ACE Group, but shot weekend scores of 73-70 to tie for fifth.
Jim Colbert, Hale Irwin and Terry Mauney are all tied for sixth place at 4-under-par, two shots off the lead.
Irwin is in search of his Senior Tour-leading 30th career title. He currently shares the top spot with Lee Trevino.
Colbert nearly claimed win No. 20 last week in Mexico. But despite a second-round 62, the 59-year-old finished one shot back of McCullough.
Defending champion Allen Doyle is three shots off the 18-hole lead after posting a 3-under-par 68 at the Newport Beach Country Club.
See Full-Field scores from the Toshiba Senior Classic here.