Oil in radiator and overflow bottle

[shreck]

I went to change my oil the other day and noticed that there is oil in my overflow bottle for the radiator and in the top of the radiator. How serious is this. If I just change the fluid and flush it out is it possible to come back. Oh btw I always smell antifreeze but the fluid is hardly going down.

Please advise what I should do. I would like to keep this van as long as possible without spending too much money as I am looking to get new wheels next year.

[LMP]

...usually, it is the other way around...that is, coolant in the oil pan....Did you check for that? if you have a blown head gasket, it usually shows as kind of white foam on the inside of the oil cap....
Also, you can remove the radiator cap and run the engine..a blown gasket often show as bubbles of exhaust popping out form radiator...
SInce the history of your event is unknown , have some more test before any conclusions, and come back to tell about it

[richtazz]

you have a blown intake gasket, common problem on any and all GM 3.4 v-6's. Get it fixed as soon as possible, if it gets worse and the antifreeze starts getting into the oil, your motor will be soon toast.

[shreck]

I have never seen true evidence of antifreeze in the oil, but it looks blameworthy.

A bit of history

Last year I put a new water pump on when it started leaking around the bearing. I was loosing a lot of fluid. But even after I changed I thought it was strange that I could still smell antifreeze and was loosing fluid, but none was ever found on the ground or leaking that I could see, I even shampooed the engine. I did notice that in the extreme hot weather last year that I had to keep topping up the fluid every couple of weeks. Now this year has been pretty cool summer and I have not topped the fluid up once, however there is now a black oily ring inside the overflow bottle. The inside of the radiator cap also oil on it and there is a rind around the neck of the filler.

I have been changing the oil every 4 weeks now weather it needs it or not to help slow down any damage that might be getting done to the internals. The oil is usually black or brownie colour and it is on the watery side, no foam is evident in the oil at all. When I take a left corner a bit quick I can now hear a rumbling noise coming from the motor as if it were on the low side. I have always kept the oil at the proper levels. Right after an oil change the van gets more peppier and responds when it should but other times just before its time to change my monthly oil it gets sluggish and I end up getting heavier on the gas. Funny thing now I remember just before I stared changing my oil every month that my gas usage went from approx. $60 a week to $

[LMP]

...I don't like the 3.4...

[shreck]

Did it ever come with a 3.1? A guy I worked with last year really liked his 1996 3.8L until he had to put gas in and then he complained about it. Then I found out why when the bank came to work and took it back.

[LMP]

..well I thought that when the put the 3.4 in, it became the only option.

EDIT Feb 17:
Hey how interesting jnp59! That is something rarely heard of , but a real possibility that is seldom considered ! Good to remember !

[shreck]

I am not too sure as I cant find a manual for a 96 to find out what they came with or without!

[jnp59]

I had the same problem last summer and it was the transmission cooling lines that run thourgh the radiator. I replaced the radiator and that solved my problem. I have a 94 Trans Sport.

[eleveniron]

ARRGH! I just logged in here to post a question about my coolant in my oil on my 97 (and visa versa) TransSport...all of it. The low coolant light came on this morning. After I put 4 litres in I pulled the dipstick and there it was...WAY too high!

My first guess was head gasket. Guess I'll find out soon enough.

For the guys with small amounts of foam or sludge at the rad filler neck or on the cap...there is a GM service bulletin for this. They state that it is normal and to make sure the rad is always full and that should eliminate the small amout of sludge.

[GTP Dad]

It doesn't necessarily have to be a head gasket. Could be that the intake manifold gasket has gone bad and is leaking coolant into the oil. I would check that before I continued to pull the heads. Once you remove the intake manifold gasket if it is leaking you will see spots of water or antifreeze in the area of the lifters.
As far as Shreck's question the oil may indeed be coming from the transmission. I don't know if he has been using dexcool or not but that could be what is causing the oily looking residue also. Since there is no water in the oil there are two possibilities, bad head gasket or bad transmission cooler. Good Luck to both!

[eleveniron]

Yeah, after some more reading last night it definately sounds like I'm looking at lower and upper intake manifold gaskets. Guess I know what I'm doing this weekend.

Before I jump into it, has anyone here pulled the intake manifolds off a 97 trans sport? anything nasty I should be prepared for or is everything accessable enough?

Thanks!

[shreck]

I guess a little update is due. Dusty (Dustbuster) is gone to the boneyard at the end of the road.

In late November early December when the temp dropped to about -2 3+ the bottem end of the motor started making a loud klanking noise in the bottom end, and when I went around corners it got even louder with a slightly different klank. When the motor warmed up it would go away to a slight rap, I checked the oil a couple of times after the noise started and there was a thick brownie yellow resadue. I knew at this point it was going to cost big bucks for the repairs with the damage that has probly deen already done to the internals. The power is also reduced and I would find it having trouble climbing hills. So I decided to get rid of it directly to the wreckers for a wopping $150.00 cdn thats about two nights worth of pizza, as I could not store it until I had time to pay it any attention.

It cost me $2300.00 to pick up a really good used car probable for a lot less than it would cost for the repairs to the van. Don't get me wrong I miss the big brute, it did a lot of hauling the family around camping and all.

[eleveniron]

Just finished changing the intake manifold gaskets. Wasn't too bad of a job. What a friggin mess though...all the sludge and trying to drain that goo out of the oil pan when it is barely above freezing in the shop.

The only surprise was having to remove all the push rods to change the gaskets...the shop manual never mentioned that.

The whole job took me about 12 hours.

Steve