Vortec V8 Coolant leak

[JCF350]

Re: Vortec V8 Coolant leak

Oh and one more thing, if DexCool doesn't cause the intake manifold leaks on the Vortec engines, how many of you guys have had the ones on you raw water cooled marine engines leak? I had my intake manifold off my 1997 5.7 with over 500 hours on it, and the intake manifold gasket was perfect. I'll bet if it was in a GM truck with DexCool, and had 70,000 miles on it, it would have been leaking.

Different temps = different expansion and contraction rates. The replacement gaskets allow the intake manifold to move a bit more. Ever pulled those manifolds and looked at the gaskets. The only corrosion you see is from those that have been leaking for while. The problem with the intakes started when they went to the new design manifolds. Same thing with the heater hose connection at the intake manifold, first it leaks then starts sucking air around it causing the corrosion. If you are going to maintain a vehicle yourself then you need to keep up with the service bulletins that come out for your vehicle from the factory just like the dealer tech's do. Also sometimes they'll issue a bulletin (like the coolant level) to deal with people that would say "well it's just a little below the full mark so I'll let go till later" so that people will keep the dam thing full.

 

[Gary H NC]

Re: Vortec V8 Coolant leak

The updated gaskets are metal with a hard rubber like coating.The OEM gaskets were just regular old paper type gaskets that got brittle and stopped sealing.
My opinion is the Dex-Cool didn't have a darn thing to do with it.Mine still looked like new anti-freeze but i do flush and refill it every 40k or so..
OK...bash away!!

 

[Caveman Charlie]

Re: Vortec V8 Coolant leak

....

 

[TilliamWe]

Re: Vortec V8 Coolant leak

I guess I should sue the company that was contracted to service the vehicle while it was a company car, then? Cause I didn't maintain it, the leasing company dictated major national service chains that were to service the vehicles. It's still bull that TSBs as stupid as "overfill" the fluid reservoir have to be issued, don't you think?
I didn't see the gasket on my 3.4, but heard rumors that somewhere in between 2003 & 2004 (how many years after the problems started was that? 4 or 5???) they switch to an improved gasket at the factory. Must have done something right, my 04 Impala with 104,000 doesn't have any coolant loss issues, yet. But I also removed, and flushed the DexCrap out at 68k miles. (right after I bought the car from the company)
The intake manifold gasket on my Mercruiser 5.7 was a thick black plastic with just rubber "rings" around the ports. Is that the better gasket?
OK, so DexCool doesn't cause the coolant leak (for all you Kool Aid drinkers out there), but a Poorly designed gasket does, right? How is that any better? GM still screwed up, royally!

 

[JCF350]

Re: Vortec V8 Coolant leak

All car company's have screw ups. The big screw up here was GM not taking care of the gasket (and hose) issue and let their customers eat the repair. Ford did the same stupid thing thing with the 4.6 (intakes cracking open and leaking coolant). Ford has since reimbursed their customers however. Don't know if the GM bean counters have seen the light or not.

Here is another example of this. Honda had their distributors failing in the Accords from 1990-1992 (upper bearing failing because of imbalance in the distributor shaft) at right around 80,000 miles. This took a class action suit from the owners to rectify, incidentally the problem continued through to the 94 models but Honda fixed them right away.

Stuff like goes on with all car companies. Just a matter of whether or not they take care of their customers.

 

[dave4151]

Re: Vortec V8 Coolant leak

I have to agree with Gary since I just went through this on my wife's 4.3 Jimmy.

Get the lower intake manifold gaskets replaced as soon as you can. It will only get worse and once it does you will be pumping antifreeze into your oil.

If you go to the GM section of an automotive forum and search "lower intake manifold gasket" you should find a bunch of information.

 

[ehenry]

Re: Vortec V8 Coolant leak

OK, To all the gloom and doomers that said I was going to have to plunk down 100's of bux................

It turned out to be the water pump gasket on the passenger side. $60 for a new pump (since the old one had 106K miles on it but was still working fine), a tube of sealer, a gasket that came with the new water pump and a couple hours of my time......I'm tooling back down the road.

Just hate the price of gas went back up.....i'm not tooling as much as i was.

Thanks to all that replied.

 

[Gary H NC]

Re: Vortec V8 Coolant leak

Thats great! Glad it was an easy fix. Gas jumped up here like crazy too..

 

[Caveman Charlie]

Re: Vortec V8 Coolant leak

OK, To all the gloom and doomers that said I was going to have to plunk down 100's of bux................

It turned out to be the water pump gasket on the passenger side. $60 for a new pump (since the old one had 106K miles on it but was still working fine), a tube of sealer, a gasket that came with the new water pump and a couple hours of my time......I'm tooling back down the road.

Just hate the price of gas went back up.....i'm not tooling as much as i was.

Thanks to all that replied.

Great that is was a easy fix. But[ as one of the gloom and doomers] this is the exact sort of problem that causes the dexacool to break down and start eating everything else. This is still the perfect time to get everything flushed and put in new antifreeze. It's time anyway.

 

[TilliamWe]

Re: Vortec V8 Coolant leak

Glad it was that simple. But you flushed it all out and got rid of the DexCool, right?

 

[dolluper]

Re: Vortec V8 Coolant leak

Good fer you ,was that the original pump you replaced ??? if so I hope you kept it as a spare.....better Q than replacements

 

[NeverEnough02]

Re: Vortec V8 Coolant leak

I have 130k+ miles on my 4.8 and it take a HEAVY beating. At 80k my rotors and pads were oem with the shocks tires and battery. (I think the plugs were changed once). I needed a rear rotor at that point so I switched them all out the Baer and completed the maint. My rear tires wear out quick and the fronts always look new (again the lead foot). These trucks last for a very very long time without issues at all. Just keep the fluid levels correct and the thing will keep going. In tank fuel pump is about all you have to worry about on a maintained silverado. Glad you got her fixed!

 

[cbear34]

Re: Vortec V8 Coolant leak

Glad you got it fixed relatively easily.
The intake gasket leaking coolant has always been a Chevy problem. I had to replace the intake gaskets on my 94 K1500 Blazer a couple of years ago, 113,000 miles. I religiously change all my vehicles fluids. When I was an auto mechanic over 20 years ago, that would be one of the leak areas I would always check. Just keep an eye out for that.

 

[PierBridge]

Re: Vortec V8 Coolant leak

The updated gaskets are metal with a hard rubber like coating.The OEM gaskets were just regular old paper type gaskets that got brittle and stopped sealing.
My opinion is the Dex-Cool didn't have a darn thing to do with it.Mine still looked like new anti-freeze but i do flush and refill it every 40k or so..
OK...bash away!!

Correct other than the old gaskets are plastic not paper nothing to do with the coolant.

 

[dolluper]

Re: Vortec V8 Coolant leak

I agree carp gaskets fer sure

 

[Gary H NC]

Re: Vortec V8 Coolant leak

Probably correct on the plastic OEM gaskets.They did crumble when i tried to remove them..
The updated gaskets are about 2 times thicker and look really heavy duty!