Oil in coolant
Hi everyone.
I'm new to forum life.
Just got my first Camaro 2001, 3800 v6. Noticed oil in coolant and trany pan leaks, needs new gasket. I don't have a book on it yet but don't want to drive if oil is seeping into my coolant from somewhere, I don't know anything about this engine. I've read that it could be from my transmission but it looks brown and it is oily. otherwise the car runs fine and no over heating issues, Help??
I'm new to forum life.
Just got my first Camaro 2001, 3800 v6. Noticed oil in coolant and trany pan leaks, needs new gasket. I don't have a book on it yet but don't want to drive if oil is seeping into my coolant from somewhere, I don't know anything about this engine. I've read that it could be from my transmission but it looks brown and it is oily. otherwise the car runs fine and no over heating issues, Help??
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Most likely it is not oil in the coolant, Its the Dex Cool GM put in there for coolant. It has a brown mud look to it and it is very common on a car that needs a coolant flush. You will never get it all out either. In my project 96 I flushed the engine while it was out with a hose and the radiator and I replaced all the stock hoses and changed the coolant twice and I would still get some of the old brown stuff in the over flow.
The biggest problem it will cause will be sediment in the radiator. I have seen radiator half full of the mud. With the radiators that full over heating becomes a problem.
Its been pretty common for people to think its oil in the coolant but your 3800 has no pressurized passages through the heads or intake like an over head Cam engine would. The only way to get oil into the coolant would be a crack in the block/heads or intake. That would allow oil into the coolant when the engine was cold but it would also allow coolant into the oil when hot. This would render a engine not savable in a matter of hours. If your oil is clean or even black your good. If your oil is a brown milkshake you are screwed.
As long as your oil is still oil just flush your coolant and watch the heat. If the engine is running out of spec hot either keep flushing or replace the radiator.
The biggest problem it will cause will be sediment in the radiator. I have seen radiator half full of the mud. With the radiators that full over heating becomes a problem.
Its been pretty common for people to think its oil in the coolant but your 3800 has no pressurized passages through the heads or intake like an over head Cam engine would. The only way to get oil into the coolant would be a crack in the block/heads or intake. That would allow oil into the coolant when the engine was cold but it would also allow coolant into the oil when hot. This would render a engine not savable in a matter of hours. If your oil is clean or even black your good. If your oil is a brown milkshake you are screwed.
As long as your oil is still oil just flush your coolant and watch the heat. If the engine is running out of spec hot either keep flushing or replace the radiator.
Most likely it is not oil in the coolant, Its the Dex Cool GM put in there for coolant. It has a brown mud look to it and it is very common on a car that needs a coolant flush. You will never get it all out either. In my project 96 I flushed the engine while it was out with a hose and the radiator and I replaced all the stock hoses and changed the coolant twice and I would still get some of the old brown stuff in the over flow.
The biggest problem it will cause will be sediment in the radiator. I have seen radiator half full of the mud. With the radiators that full over heating becomes a problem.
Its been pretty common for people to think its oil in the coolant but your 3800 has no pressurized passages through the heads or intake like an over head Cam engine would. The only way to get oil into the coolant would be a crack in the block/heads or intake. That would allow oil into the coolant when the engine was cold but it would also allow coolant into the oil when hot. This would render a engine not savable in a matter of hours. If your oil is clean or even black your good. If your oil is a brown milkshake you are screwed.
As long as your oil is still oil just flush your coolant and watch the heat. If the engine is running out of spec hot either keep flushing or replace the radiator.
The biggest problem it will cause will be sediment in the radiator. I have seen radiator half full of the mud. With the radiators that full over heating becomes a problem.
Its been pretty common for people to think its oil in the coolant but your 3800 has no pressurized passages through the heads or intake like an over head Cam engine would. The only way to get oil into the coolant would be a crack in the block/heads or intake. That would allow oil into the coolant when the engine was cold but it would also allow coolant into the oil when hot. This would render a engine not savable in a matter of hours. If your oil is clean or even black your good. If your oil is a brown milkshake you are screwed.
As long as your oil is still oil just flush your coolant and watch the heat. If the engine is running out of spec hot either keep flushing or replace the radiator.
Last edited by woof2001; Mar 25, 2020 at 10:30 AM. Reason: another question
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You could get coolant dripping outside of the motor or coolant going into the oil. With just about any gasket, if you see stuff coming out of it its a problem but if your edge around the gasket is clean and perfect the gasket could be shot and there is NO correlation between looks of the outside of a head gasket and if the inside of the gasket is shot. We don't have to guess with intake gaskets a quick pressure test will let you know if you have a leak. You should get the coolant system checked and flushed. It would have to be a pretty small leak to have no effect on the car overheating.
Note: Lower intake gasket failure is common on 3800 to the point there was a class action lawsuit. There is no oil going through the intake gasket, only coolant. So coolant can get into the oil which is way worse the oil in the coolant. You are most likely seeing oil from the valve covers getting on the intake gasket area. With a 3800 intake even a small leak should be repaired because even a small amount of coolant in the oil will kill and engine. IMO failed intake gaskets are the number one cause of engine failure in the 3800, causing more engine replacements then all other issues combined. I would assume that most on the road 3800 have had the intake gasket done already, this was not a design issue as much as GM just cheaped out on the gasket material. Once the job is done it should last the life of the motor.
If you system has a lot of the dex-cool mud in it you should replace the thermostat after the system is flushed.
Note: Lower intake gasket failure is common on 3800 to the point there was a class action lawsuit. There is no oil going through the intake gasket, only coolant. So coolant can get into the oil which is way worse the oil in the coolant. You are most likely seeing oil from the valve covers getting on the intake gasket area. With a 3800 intake even a small leak should be repaired because even a small amount of coolant in the oil will kill and engine. IMO failed intake gaskets are the number one cause of engine failure in the 3800, causing more engine replacements then all other issues combined. I would assume that most on the road 3800 have had the intake gasket done already, this was not a design issue as much as GM just cheaped out on the gasket material. Once the job is done it should last the life of the motor.
If you system has a lot of the dex-cool mud in it you should replace the thermostat after the system is flushed.
Last edited by Gorn; Mar 25, 2020 at 11:39 AM.
You could get coolant dripping outside of the motor or coolant going into the oil. With just about any gasket, if you see stuff coming out of it its a problem but if your edge around the gasket is clean and perfect the gasket could be shot and there is NO correlation between looks of the outside of a head gasket and if the inside of the gasket is shot. We don't have to guess with intake gaskets a quick pressure test will let you know if you have a leak. You should get the coolant system checked and flushed. It would have to be a pretty small leak to have no effect on the car overheating.
Note: Lower intake gasket failure is common on 3800 to the point there was a class action lawsuit. There is no oil going through the intake gasket, only coolant. So coolant can get into the oil which is way worse the oil in the coolant. You are most likely seeing oil from the valve covers getting on the intake gasket area. With a 3800 intake even a small leak should be repaired because even a small amount of coolant in the oil will kill and engine. IMO failed intake gaskets are the number one cause of engine failure in the 3800, causing more engine replacements then all other issues combined. I would assume that most on the road 3800 have had the intake gasket done already, this was not a design issue as much as GM just cheaped out on the gasket material. Once the job is done it should last the life of the motor.
If you system has a lot of the dex-cool mud in it you should replace the thermostat after the system is flushed.
Note: Lower intake gasket failure is common on 3800 to the point there was a class action lawsuit. There is no oil going through the intake gasket, only coolant. So coolant can get into the oil which is way worse the oil in the coolant. You are most likely seeing oil from the valve covers getting on the intake gasket area. With a 3800 intake even a small leak should be repaired because even a small amount of coolant in the oil will kill and engine. IMO failed intake gaskets are the number one cause of engine failure in the 3800, causing more engine replacements then all other issues combined. I would assume that most on the road 3800 have had the intake gasket done already, this was not a design issue as much as GM just cheaped out on the gasket material. Once the job is done it should last the life of the motor.
If you system has a lot of the dex-cool mud in it you should replace the thermostat after the system is flushed.
Glad I read this. I have the same problem with my 2000 Z28. Car is new to me and I checked the overflow bottle and OMG found it full of brown muddy sludge. There is no sign of water or coolant in the oil. How best to flush the system ???
I found with Dex cool the best way to get it all out is just take it to a shop for a coolant flush, it can get really thick and really cake into the radiator, it's not too expensive to get it flushed at a shop that have flushing machines


