change dexcool in low mileage Buick?

[Noah]

I've got a 2002 Buick Century 3.1L with only 17K miles. The AF is discolored/dirty while not-sludgy, and there's no LIM gasket failure that I detect. It's driven about once a week.

Should I switch to another kind of antifreeze? I've read many dozens of posts, and it seems nothing is certain. E.g.:

if I switch, will that make things worse because you can't get every trace of dex out and it will mix with the new stuff and cause sludge.

is it years or miles that matter? If it's not years, why not - if the gasket has been in contact with the AF all along?

is it dex that's corrosive or the sludged-up dex that's corrosive to the plastic gaskets?

So what it seems to come down to for me is that last question above. Hasn't any agency or person just taken a plastic gasket of the vulnerable OEM type, soaked it in fresh dexcool for a time and seen what happens? Maybe also soak another sample in the sludgy dex and compare that. Nobody such as consumer reports or the class action attorneys have done that? Heaven forbid that GM would share any info.


And fwiw, here's a video of my opened radiator:
http://www.vimeo.com/9581517

If anybody has any comments on the color, I'd appreciate it since I'm partly color blind. Does it look like what you'd expect the original dexcool to have turned into? I got the car used at 4 yrs old and am *assuming* it had never been changed.

 

[Chris142]

Its past due to be changed. I'd change it out. BTW the rubber seal on your radiator cap is swelled out making the cap defective.

 

[Bob Woods]

Dex cool will work fine if it is changed on time and never has anything else added to it.

 

[pbm]

Originally Posted By: Chris142
Its past due to be changed. I'd change it out. BTW the rubber seal on your radiator cap is swelled out making the cap defective.


How can you tell the seal is swelled out?


I also have a 2002 Century and I believe the 2-EHA in the Dexcool (new or used) causes softening of the gasket after some time. I used Prestone AMM which is a Dexclone but I plan on using PEAK Global next time. I changed the L-I-M gasket at approx. 80K and I now have 114K. The car runs like new and has been quite troublefree.

 

[Chris142]

Originally Posted By: pbm


How can you tell the seal is swelled out?



I can see the rubber in the video. It's much larger than it should be and has a deep groove where it seals on the radiator. Anytime the rubber is swelled past the metal the cap needs to be replaced. .08 seconds into his vid.

 

[mechanicx]

Ley me try to address all your questions.


Originally Posted By: Noah
I've got a 2002 Buick Century 3.1L with only 17K miles. The AF is discolored/dirty while not-sludgy, and there's no LIM gasket failure that I detect. It's driven about once a week.


It may not be leaking now because the miles are so low but it will fail. Look for leakage at the engine ends under the throttle body and at the other end of the manifold. An UOA would also indicate if there was a coolant leak.



Quote:
Should I switch to another kind of antifreeze? I've read many dozens of posts, and it seems nothing is certain. E.g.:

if I switch, will that make things worse because you can't get every trace of dex out and it will mix with the new stuff and cause sludge.


I think you should switch because the cap on the radiator system and the potential leaking manifold is causing sludge. You need to get all the old coolant out and get a full charge of new coolant in, whether Green or G-05.

Quote:
is it years or miles that matter? If it's not years, why not - if the gasket has been in contact with the AF all along?


It's both years and miles. With the gasket though it's more about miles because of heat and pressure.


Quote:
is it dex that's corrosive or the sludged-up dex that's corrosive to the plastic gaskets?


Well the particular intake gasket used is not compatible with Dexcool. It's not a good gasket to begin with and would eventually leak with any coolant. Dexcool just causes it to leak a little sooner and worse, plus Dexcool doesn't tolerate air in the cooling system and can sludge.


Quote:
So what it seems to come down to for me is that last question above. Hasn't any agency or person just taken a plastic gasket of the vulnerable OEM type, soaked it in fresh dexcool for a time and seen what happens? Maybe also soak another sample in the sludgy dex and compare that. Nobody such as consumer reports or the class action attorneys have done that? Heaven forbid that GM would share any info.


The are some SAE papers that say the material used for this intake gasket, silicon, is not very compatible with the coolant. An expert witness in the GM lawsuit said the gasket wasn't compatible. The Felpro problem solver gasket is made wih a steel back and more solid plastic seal of a different material.

Quote:
And fwiw, here's a video of my opened radiator:
http://www.vimeo.com/9581517

If anybody has any comments on the color, I'd appreciate it since I'm partly color blind. Does it look like what you'd expect the original dexcool to have turned into? I got the car used at 4 yrs old and am *assuming* it had never been changed.


The coolant is past due being changed, but Dexcool should not look like that if everything is in good order. You should flush the coolant out. change the cap to a Stant 10230 or 11230 that has a spring center.

 

[Rock_Hudstone]

As mentioned, the lower intake manifold gasket will likey fail eventually and it may not be a visible external leak. The gasket can also fail and leak coolant into the crankcase. Always check the inside of the oil fill cap, valve cover area, and the PCV valve for sludging at every oil change.

However, replacing the Dex-cool now may buy more time. For example our 1995 Olds Cutlass, (last year for conventional green coolant in GM vehicles), went over 150,000 miles before the LIM gasket needed replacement, it now has 210,000 miles. Whereas, my mother's 1999 Monte Carlo LIM gasket failed at around 60,000 miles on Dex-cool and was sludged up pretty bad.

Don't worry about switching from Dex-cool to conventional green coolant, etc, just make sure to flush the system well.

Open the radiator drain plug and disconnect one end of the coolant bypass hose. Using a garden hose with a pistol grip noozle alternate the water stream between the radiator fillcap opening and the open bypass hose back flushing until the water runs clear. I suggest Peak conventional green coolant and follow the proper coolant fill procedures.

 

[Noah]

Originally Posted By: Rock_Hudstone

Open the radiator drain plug and disconnect one end of the coolant bypass hose.

Thanks kindly for all the replies. Since the weather has turned warm, I set about to do this today - but I can't find the drain plug. Facing the engine compartment, the side tank to my left has the two lines for the transmission fluid cooling. There doesn't seem to be room under the lower line for a drain to be there.

On the right side tank, I've felt around over and over but can't locate the drain on that side, either. Or in the middle anywhere. It's nearly impossible to actually see anything by laying on the ground. Things are just too crowded.

I assume the drain would be on the side of the radiator that faces the engine - not the side that faces me when I'm standing in front of the car. Would anybody know or have a guess where it is? Thanks.

2002 Buick Century

 

[mechanicx]

The radiator drain is always on the driver's side. Sometimes it is facing toward the front of car, but on your application I think it is facing toward the engine. It's probably just hard to find and blending in good with the radiator tank.

 

[Zedhed]

Nah...leave it there for 5 yrs, 100,000 miles. It's Dexcool, the savior of cooling systems. Able to withstand freezing winters in a single bound, stops corrosion faster than a speeding bullet, more powerful than a locomotive, more hyperbole, ad nauseum.

SludgeCool.....

 

[Noah]

Originally Posted By: mechanicx
The radiator drain is always on the driver's side. Sometimes it is facing toward the front of car, but on your application I think it is facing toward the engine. It's probably just hard to find and blending in good with the radiator tank.

thanks. Because of your reply, I persisted and found it. It wasn't on the side tank as I'd thought, but is on the core area.

The problem now is to get at the plug. I have to loosen or remove a plastic guard/shield that's in the way. This is a video of one of several fasteners holding that plastic shield in place. The view is with the pocket camcorder on the ground, looking straight up.

http://www.vimeo.com/10612304

It's been more than a few years since I'd worked under the hood of a car, so that thing is new to me. What's that fastener called and how do I remove it?

Btw, I decided to do a quick refill for now to get the old Dexcool out of there. Then I'll do the real deal in a couple of months when I have more time, putting in what AF I don't know yet - maybe the Prestone All Around.

NOTE: I got Prestone Dexcool ay KMart for $14 - $2 on sale = $12 There was no sign but the sale does ring up right.

That beats $16 at Advance.

There's also $2 off on other Prestone if anybody's interested, I think that the All Around stuff ends up at $11 or $12.

 

[FusilliJerry82]

I would honestly use G-05 if I were you.

 

[FL-400S]

I just changed my 02 malibu at 60k miles to Peak Global Lifetime. I think one sign of gasket leakage is some sludgy poopy brown [censored] in your overflow tank. Im not sure how oil would get in the tank if the gasket wasnt leaking.

 

[Noah]

Originally Posted By: FusilliJerry82
I would honestly use G-05 if I were you.

Thanks, Jerry. I think if I can completely flush everything, that's what I'll do in a month or so - since my understanding is that's the least corrosive to the gasket.

I've also read that various AFs are very similar to Dexcool but aren't called Dexcool, such as one of the Prestones. OATs, HOATs or whatever.

It seems to me that everything is getting too complicated. More complexity can only lead to more problems - up to and including mystery Toyota crashes.

 

[Herz]

When the gasket does fail, just use fel-pro gaskets. They are compatable with dex-cool.