GT Griller

iTrader: (7)

Well just like the title says....Ive got a 95 GMC sierra full size v8 350...Few weeks ago i changed the water pump cause it was shot...all went good...i ran for a while to get it up to temp and get any air out of the system...well i thought it everything was fine...ive put about 300 miles on it since....but i noticed about 100 miles ago that the temp was fluctuating on my way back to lubbock....it got up to normal temp 210ish..then went slightly passed..came back..then went slightly under...then went back...then went higher..then back...then under...etc....it never over heated and never got passed 220ish but it finally settled down after about 20miles at 70mph...Got to lubbock next day it was back to fluctuating....So i KNOW all the air had to have been out right...so im thinking temp sensor or thermostat...changed the stat and still fluctuates only at colder temps..stays under 210...anyone else have this issue?