View Full Version : how to change coolant in 2003 deville

05-27-06, 05:58 PM
where are the drain plugs on 03 deville? will plug drain all coolant out, where should i add tablets, where do i refill with coolant seeing there is no cap on the radiator, should i refill in surge tank? please let me know asap thanks!

05-27-06, 08:38 PM
Drain should be on the drivers side. Either on the bottom or on the back side of the radiator. That said, it is usually easier to pull the lower hose. You probably won't get all the coolant out. There will be some residual left. I find that I can get a little more out by reversing the hose on my shop vac and sticking it in the surge tank. Seal the opening with your hand and let it blow. I would not use a compressor. Your better off with high volumn, low pressure than vice versa. Put the tabs in the lower hose, not the surge tank. Slowly refill via the surge tank. Rev the engine several times to about 4K and it should purge itself of any air in the system. Top off the coolant as required. Check it again after the first drive.

05-27-06, 08:52 PM
thanks ranger! just changed used bars leak golden seal powder used two .75 now with that said is it normal that i drove to the gas station and it ran two points above the normal (halfway mark) than driving home it lowered itself a point have not checked since is that normal please let me know thanks

05-27-06, 08:59 PM
I suspect you did not rev the engine after filling the coolant and had some air in the system. That is why it ran hot. I believe the coolant temp sensor is under the intake and at a relatively high point on the engine, so if there is air in the system, that is where it will be. When the guage lowered is probably when the system purged itself. Check the coolant level again after it cools. Should be about 1 1/2" - 2" below the filler neck.

05-27-06, 09:27 PM
right on man its good to now people who know their stuff i'm gonna check right now thanks man god bless.