Hello Everyone how are you i was wondering what is the bst antifreeze is best to use for my 93 deville 4.9l Is yellow good to use because ive heard of the dexicool eating up the intake manifold gasket and seals i don't want that sosomeone please tell me is it better to use the yellow or keep using the dexicool thanks everyone.

I've been running dexcool in my '95 4.9 for 6 years now, no gasket failures yet.

I've also been running dex in my '90 4.5, though that has a vacuum leak at the intake gasket. Can't necessarily blame it on dex though. Intake gaskets were a common problem on the 4.x's long before dex came into the picture.

If there was a problem with dex, they wouldn't be using it anymore. Period. If you put two and two together, the only time coolant arguments are started is when there's common gasket failures. This is always a hot topic on multi-alloy engines. Go figure. As in the 4.9's case, aluminum intake on iron heads gives a far better chance of the intake gasket leaking than an all iron engine.

In my opinion, gasket failures are all in debt to the design they are used in or to neglect from their owner. NOT the type of liquid used to transfer heat.

the only thing I can see pouring into your cooling system to degrade gaskets is straight water. Dex is as anti-corrosive as any coolant out there. Whichever you use, drain and refill at the recommended intervals to remain problem free.

I just flushed the system about 2 months ago how often do i have to change dexicool every year or what I forget I just wanna be on the safe side but as long as long as i keep up iwith the coolant exchanges you think i should have any problems because thats one thing im crazy about keeping up with maintenance on my car.

I prefer to stay with the green stuff unless the red is factory recommended. I dont know what year they started using it... The red vs green argument is kind of like the synthetic vs conventional oil debate - you just have to gather as much info as possible and use your best judgement. The main benefit of dexcool is that it can be left in the engine much longer than the green stuff, but since these cars require such meticulous attention to the cooling system, I prefer to change the coolant once a year regardless of its condition. So using a 5 year coolant is pointless for me... I like to drain, flush, vacuum, and fill with green Prestone and distilled water plus 2 tubes of Bar's 'Gold Seal' powder once a year. I always change the thermostat and add a bottle of 'Water Wetter' at the same time. You cant put a price on peace of mind.

I believe Dex started somewhere between 95 and 96.

But anyway, like Sevillian and I have stated, all you can do is change the coolant before the end of it's useful life. If you've done that and still get a gasket leak, there was nothing you could have done differently.

Sevillians reference to motor oil was good. If you let your oil run past the end of it's useful life, the negative effects start immediately. If you let your oil go to long, bearings knock and rings lose their seal. If you let coolant go, your cooling system starts to corrode and gaskets fail. Pretty simple.

It came with green, stay with green unless you are looking for an adventure.

When the dex orange goes bad it turns into wax and coats the whole inside of the engine. You should see my dad's Taurus even after five or six flushes that junk is still around. I would never put that stuff into any of my vehicles.

So should I switch to the gold or what i want the best for my car

When the dex orange goes bad it turns into wax and coats the whole inside of the engine. You should see my dad's Taurus even after five or six flushes that junk is still around. I would never put that stuff into any of my vehicles.

that "wax" coating is exactly what is supposed to happen; it's not a sign of "going bad". Otherwise, the coolant would only protect on direct contact and no other time like when the engine is off. Green coolant did this through silicates.

In the end, it's all doing the same thing, green, gold, red, dex. There is no right or wrong. There is nothign wrong with dex, and there's nothing wrong with green or gold. Coolant's job is to transfer heat and provide corrosion protection and they all do a great job. That's it. It's not some magical formula supernatural ooze that's going to eat your engine from the inside out. Ignore all of the internet myths and scares out there. Change per recommendations/life expectancy of your coolant of choice and enjoy your ride.

So should I switch to the gold or what i want the best for my car

Mike, just use green prestone with distilled water and add two tubes of "Bars Leaks Gold Seal powder". Change it no less than every two years. That's the best you can do as far as coolant for your car.

Sevillian can i use the green even though i got dex in it but im gonna have to make sure i get all the dex out of the cooling system rite?

Yes.

Sevillian can i use the green even though i got dex in it but im gonna have to make sure i get all the dex out of the cooling system rite?

The best way to do that IMO is to detach the lower radiator hose at the radiator and stick the end of a shop vac in the hose. Or just flush and fill with distilled water several times before you put the green in. You're never going to get 100% of the dex out in one flush/fill.

Flush it and re-fill with Prestone All-Makes All Models 50/50 they sell at Wal-Mart . I do it yearly and no sealer added. Bad for the heater core.

Is switching from dexicool to the green antifreeze dexicool eats away at parts so im gonna switch over to the green antifreeze.

No anti freeze "eats away parts". That is an internet myth.

oh ok but my mechanic doesn't like dexicool and it does eat away gaskets and GM did have a lot of lawsuits over the dexicool and that isn't a myth so im switching over to green.

There is a lot more to the Dex-Cool law suit than meets the eye. Dex got a bad rap. If it ate gaskets ALL GM engines would have problems and it would be with ALL gaskets, not just HG's. Nothing wrong with green coolant. Your car came with green from the factory anyway and is what you should be using.

oh it did why does it have dexicool then did someone switch it over?

Yup, someone had to have switched it over. GM didn't go to Dex until '96.

oh well im switching it back

Just be sure to flush it good.

ok i will thanks