03 Grand Am: oil in coolant

**SteveCZ28** · 10-21-2010, 10:10 PM

hey i am stumped on what could cause oil to get into the coolant of my wifes 2003 grand am gt with the 3400 v6...she took the car to get a simple oil change, and they checked all fluids for her, and found oil in the coolant reservoir...i asked if the car is acting up or what not, and she says the car runs a little hotter than normal, but nowhere near over heating. the service shop naturally wanted to charge her 100 for a coolant flush right there on the spot, but i told her to hold off until we get whats causing this to happen fixed. so any ideas on what would cause the oil to leak into the coolant...thankfuly its oil in the coolant, instead of coolant in the oil...i made sure of that. but at this point any information, or things to look at would be helpful

**98maro** · 10-21-2010, 11:06 PM

Head gasket???

**SteveCZ28** · 10-21-2010, 11:14 PM

i dont know bout the h.g....it still runs good

**98maro** · 10-21-2010, 11:20 PM

i will run good.. but after days will get hot.. and white smog out of the exhaust..
idk thats the only thing i can think of..

**Smittro** · 10-22-2010, 01:26 AM

Worse case, could be a cracked head.. I'd say check it yourself and see that there IS in fact oil in the rez (touch it does the substance feel like grease or mud?).. It could easily be sludge from an iron block motor.. Flush it and see if it returns.. Head gaskets are not really a common problem for the 6-60.. Change (goes to the possibility of sludge not oil) the thermostat too...

**Smittro** · 10-22-2010, 01:40 AM

Originally Posted by Smittro

Worse case, could be a cracked head.. I'd say check it yourself and see that there IS in fact oil in the rez (touch it does the substance feel like grease or mud?).. It could easily be sludge from an iron block motor.. Flush it and see if it returns.. Head gaskets are not really a common problem for the 6-60.. Change (goes to the possibility of sludge not oil) the thermostat too...

Iron sludge can easily be mistaken for oil..

**35th-ANV-SS** · 10-22-2010, 05:22 AM

I agree with Smitty on this. I had the same issue on my 96 3800II a few times. It was just sludge. I flushed it and it was fine. I hope that's your issue.

**SteveCZ28** · 10-22-2010, 07:44 AM

will this iron sludge cause the motor to run a little warmer than normal??

**SteveCZ28** · 10-22-2010, 07:46 AM

any chance or possibility it could be lower intake gaskets? as thats what came up on google

**35th-ANV-SS** · 10-22-2010, 08:56 AM

Originally Posted by SteveCZ28

will this iron sludge cause the motor to run a little warmer than normal??

I would have to say yes. Any degradation to the coolant and its properties is going to have an adverse affect on how it works.

Also check to make sure your fans are working and are coming on properly.

When is the last time the coolant was changed?

**Smittro** · 10-22-2010, 09:28 AM

Originally Posted by SteveCZ28

will this iron sludge cause the motor to run a little warmer than normal??

Sure can. Can cause hot spots too.. Including gumming up your t-stat..

Originally Posted by SteveCZ28

any chance or possibility it could be lower intake gaskets? as thats what came up on google

Could very well be..

Effected vins and rpo (Grand Am)

3.1L or 3.4L V-6 Engine (VINs J, E - RPOs LG8, LA1)

Originally Posted by 35th-ANV-SS

I would have to say yes. Any degradation to the coolant and its properties is going to have an adverse affect on how it works.

Also check to make sure your fans are working and are coming on properly.

When is the last time the coolant was changed?

This..

**bdub2145** · 10-22-2010, 09:43 AM

if there is oil in the coolant it could be the trans cooler in the radiator. headgaskets usaully will get coolant in the oil . also the lower intake gaskets can leak internally into the oil but again there would be coolant in the oil not the other way around. and fel pro makes an updated steel gasket with rubber around the sealing parts for the intake . they are the perma dry plus gaskets..

**Smittro** · 10-22-2010, 09:46 AM

3400 ohv lower intake gaskets..

These are the effected areas..

**bdub2145** · 10-22-2010, 09:52 AM

yes but again when they leak there it ends up outside the engine or in the oil giving you that chocolate milkshake look

**Smittro** · 10-22-2010, 09:54 AM

Originally Posted by bdub2145

if there is oil in the coolant it could be the trans cooler in the radiator. headgaskets usaully will get coolant in the oil . also the lower intake gaskets can leak internally into the oil but again there would be coolant in the oil not the other way around. and fel pro makes an updated steel gasket with rubber around the sealing parts for the intake . they are the perma dry plus gaskets..

Could be getting in when it's not running.. High 2-valve 660's bath the valve stem heads and springs in a pool of oil which then over flows the head and runs back into the motor right next to the coolant gasket jackets.. As the engine cools suction is created on the cooling system and could actually be "sucking" up oil pooled on and around the gasket itself..

But I'm leaning more towards iron sludge..

**bdub2145** · 10-22-2010, 09:58 AM

ok lets look at oil pressure . when the car is running the oil pressure is more than the pressure in the cooling system . now after the engine has been running and builds pressure in the system when you shut the car off it will bleed down into the engine

**bdub2145** · 10-22-2010, 09:59 AM

but yes i would say do a coolant flush and see if it comes back .

**Smittro** · 10-22-2010, 10:03 AM

Originally Posted by bdub2145

yes but again when they leak there it ends up outside the engine or in the oil giving you that chocolate milkshake look

A 660 would die long b4 ever seeing "milk shake" on the stick..

**Smittro** · 10-22-2010, 10:06 AM

Originally Posted by bdub2145

ok lets look at oil pressure . when the car is running the oil pressure is more than the pressure in the cooling system . now after the engine has been running and builds pressure in the system when you shut the car off it will bleed down into the engine

Yes but the high valve 3400 ohv does not have oil drain backs in the heads.. The cylinder head return oil flow runs in dirrect contact with LI-gasket.. I understand how the 660 works

..
<---------- see sig