A gas turbine engine guide vane heat exchanger has guide vane heat exchanger including electroformed fluid channels in electroformed heat exchanger tubes or a heat exchanger core disposed within airfoil. Non-flammable heat conducting liquid or non-metallic foam may fill space between tubes or core and airfoil. Fluid circuit may include channels within electroformed heat exchanger tubes or the heat exchanger core and extend from inlet manifold to outlet manifold for directing fluid or oil through channels and include fluid or oil supply inlet connected to inlet manifold for receiving the fluid or oil flowed into inlet manifold and a fluid or oil supply outlet connected to fluid or oil supply outlet for discharging fluid or oil flowed out of fluid or oil outlet manifold. Heat exchanger tubes or heat exchanger core, inlet manifold, outlet manifold, supply inlet and supply outlet may be integrally and monolithically electroformed together.