Alero coolant sludge problem

[bruno4]

Our April 02 Alero 3.4 V6 has done 36K miles. We purchased it as the second owners in April 03 and 22K miles. About 2 months ago, I noticed that in the coolant expansion tank, a brown sludge appeared on the base of the filler cap and on the top and sides of the expansion tank itself. As the Dexcool is supposed to last 150K miles, I was reluctant to drain and change it. Therefore, I flushed the expansion tank and refilled it with the correct ratio of Dexcool and water, but the sludge is happenning again.
This is my first time using Dexcool, is this normal? sludge to me is an enemy and should be flushed out.
Can anyone help here? Thanks in anticipation.

[Duby]

Originally Posted by bruno4

Our April 02 Alero 3.4 V6 has done 36K miles. We purchased it as the second owners in April 03 and 22K miles. About 2 months ago, I noticed that in the coolant expansion tank, a brown sludge appeared on the base of the filler cap and on the top and sides of the expansion tank itself. As the Dexcool is supposed to last 150K miles, I was reluctant to drain and change it. Therefore, I flushed the expansion tank and refilled it with the correct ratio of Dexcool and water, but the sludge is happenning again.
This is my first time using Dexcool, is this normal? sludge to me is an enemy and should be flushed out.
Can anyone help here? Thanks in anticipation.

As far as this stuff goes I haven't had that problem yet... I purchased mine used and maybe this was corrected before I took delivery. This is a common occurence and it does not seem like Olds. has done their research on this... yes sludge is bad, how to get rid of it... check with the dealer for a switch... but I have a feeling that this will be at your cost.

[petey_z24]

lots of ppl fluch out the dexcool and replace with normal green stuff. Over at s10furums.com they talk about doing this all the time without any problems afterwords

[JTrujillo86]

I would refrain from going the way of the green stuff. I used to have a Malibu, which has the 3.1 V6, which is nearly the same as the 3.4. My neighbor also had the same vehicle I did. He chose the green stuff and I stuck with Dexcool. About 2 weeks after his switch, his water pump took a dump. The mechanic attributed it to the green stuff.

Jeremy

[jamcllw]

lower intake manifold gasket leak it's notorious in 3.4L motors
your oil and coolant is mixing not a good thing
hope your under warranty because it costs around $800 to fix

[DamienZ28]

Bingo brown sludge in the cap means one thing.. OIL whick on a 3.4 means one other thing.. intake gasket! Mabey it could be a bad head gasket or a cracked head since you were not the first owner but more than likely its the intake gasket. Have looked arounf the intake for any wetness? When they get bad enough you'll see it! Good Luck don't forget to post a answer TY!

[whdream]

I agree that sludge was in my reservoir as well.
the coolant was that not so lovely brown colour. I did take it in and they told me it was in fact the intake manifold. They did replace it, And so far it has been ok. The price was pretty steep. But again, I called GM Canada, and got something worked out with them. This was a problem with GM Alero's and they were in fact doing a what the call "Good Will" deal with customers. I paid the warrenty rate. which all in all I pai 400 bucks. Rather than over 900. So ask your delearship if they can help you on this, if not call GM headoffice.

Originally Posted by DamienZ28

Bingo brown sludge in the cap means one thing.. OIL whick on a 3.4 means one other thing.. intake gasket! Mabey it could be a bad head gasket or a cracked head since you were not the first owner but more than likely its the intake gasket. Have looked arounf the intake for any wetness? When they get bad enough you'll see it! Good Luck don't forget to post a answer TY!

[oldmike]

I have the same problem as all the people above. Just bought a used 01 Alero 3.4 v6 (well, actually wrecked) and am starting the process of fixing it up. I always check mechanicals before starting body work. Noticed immediately that the reservoir tank was full of brown sludge. I'm going to take it off and clean it and while it's off, flush rest of system. Anyone have tips on how to do this? Also, how long can you run the car without the sludge causing problems? May be a while before I get around to taking it in or trying it myself. I'm definitely going to check out the "good will" fix that whdream mentioned. Looks like to me it should be a recall.
Thanks,
Mike

[DamienZ28]

I am the master of putting things off! Well reallyw ith work I haven't had time to do it my self and I normally will refuse to pay a dealer ship or mechanic to do it! BUt your right it really should be a recall! Before attempting to do a flush and fill to clean your system out I would replave that intake gasket first! The sludge will just come back if you dont. Good Luck!

[jamcllw]

The gaskets themselves aren't hard to change just very time consuming and very easy to get lost in the project. If you decide to do it yourself take your time and make sure you label everything so when you are putting it back together you don't have to search for the connections.

[whdream]

As per the "Good Will" fix by GM. This does have requirements. They go by the milage of course, and the year of car. Mine was a bit over the milage requirements, but seeing how I had called before they honored this. They did the leg work and called the dealership for me. And set things up. Make sure you get your car in soon. I had a lot of phone calls to go through to get this done.
And to be honest I don't really feel any difference in the performance of my car. Other than the smell of coolant.

Originally Posted by whdream

I agree that sludge was in my reservoir as well.
the coolant was that not so lovely brown colour. I did take it in and they told me it was in fact the intake manifold. They did replace it, And so far it has been ok. The price was pretty steep. But again, I called GM Canada, and got something worked out with them. This was a problem with GM Alero's and they were in fact doing a what the call "Good Will" deal with customers. I paid the warrenty rate. which all in all I pai 400 bucks. Rather than over 900. So ask your delearship if they can help you on this, if not call GM headoffice.

[95ragtop]

Agree with jamcllw. It's not that hard, just time consuming. I had the same problem. It took a long weekend and $35 in parts from E-bay. If you don't have a GM service manual, try the Autozone.com repair guide. They're straight from the service manual. Just don't let i go too long, eventually you'll have coolant in the oil and it will be all over.

PS. Some of the guides tell you to "rotate the engine". I skipped that part and had no problems. Good luck.

[jamcllw]

I never heard about rotating the engine. I guess I skipped that part too.

[DamienZ28]

Well I jinx myself in this post about the head gaskets.... My wifes 99 Montana witht he 3.4 lost a head gasket and its a bear of a job! I will never do this job myself again! Be warned! Its really a tough job. If it was on my alero id be done already at the same amount of time it took to get the montana's motor half apart!

[scrt79]

yup, definately intake gskts.... after you replcace them, or i should say, DURING... make sure to get the NEW updated bolts... and torque them to specs... the gskts have changed, and the bolts have also. after you replace them, i have heard of the coolant swap as well, might do you good.