I Have A 99 Deville Concours Which Needs A Motor .can I Use A Motor From A Seville Or Eldorado.. I Know That A Deville Motor Won T Go Into A Concours.. The Deville Has The Letter (y) In The Vin .someone Told Me I Can T Use That Motor In A Con. Does Any One Know For Sure...... Thanks For The Help....

You will need to replace your engine with a L37 or VIN 9 engine. And it must be from a 1996-1999 car. So your choices are an ETC, STS or Deville Concours from those years.
What is wrong with the current engine?

my car runs hot. i changed water pump,hoses, belt, cooling fan turn on and seem strong. then when i turn car off it over flows...this car has a temp. gage the needle goes from norm. to just before the red then goes back to norm..bafore this problem needle stayed at norm. and never moved...

thanks for help

Have you checked for a blown headgasket? NAPA sells a coolant test kit that checks for hydrocarbons in the cooling system. It's around $50. If it is a blown head gasket, have you considered fixing it, instead of replacing the engine?
Also, GM now sells rebuilt Northstars.

Have you ever replaced the thermostat?

Have you checked for a blown headgasket? NAPA sells a coolant test kit that checks for hydrocarbons in the cooling system. It's around $50. If it is a blown head gasket, have you considered fixing it, instead of replacing the engine?
Also, GM now sells rebuilt Northstars.YES BUT I WAS TOLD THAT YOU CAN T FIX HEADGASKETS ON NORTHSTAIR... BECAUSE OF HEAD BOLTS :runaround: THERE S NO WATER IN OIL OR WHITE SMOKE NO SIGN OF ANTI FREEZE ON SPARK PLUGS....

Have you ever replaced the thermostat?YES TWICE

This does not belong in the open forums, I am moving this to the parts/cars, sale exchange.