i was checking the coolant because i put in a new radiator and i found oil in the coolant i dont know if it is oil or transmissoin fluid but it did not do this before the new radiator so im thinking it could be the radiator or could it be something else:banghead::banghead::banghead::banghead::bangh ead::banghead::banghead::banghead:

blown head gasket or cracked engine block?

like i said it did not do it before i put a new radiator in it and there is no water in the oil

no cel an it only has 79k on it

no cel an it only has 79k on it

Could be the tranny coil in the radiator is leaking. If you have an air compressor and can remove the tranny lines from the radiator, do so and put compressed air to the fittings and see if you get air bubbles from the radiator . If you do then the coil is leaking into the coolant.

im actually hoping it is that is there any way to tell if it is oil or transmission fluid in the coolant before i start taking it apart?

What year Aurora is this and which engine?

1999 4.0 northstar

i just replaced the radiator thats why i think it that but if its something else i dont know hat im going to do
:runaround:

did you ever put any kind of stop leak in the old radiator? some brands can make the fluid milky. of course a blown headgasket can let compression get in the cooling system, and cause a radiator leak. why did you replace the radiator?

because the plastic was cracked and it is brown not milky

Dexcool can wind up in that condition also if allowed to mix with air for too long, not uncommon.

that is what it looked like when i took it out yesterday







http://i103.photobucket.com/albums/m148/wadedark/DSC01011.jpg

that looks like tired wore out dexcool

it was only a month old i put new stuff i and well see what happens

ithink i found the problem the cap went bad:rolleyes:

i think the cap was bad for some reason