1995 Pontiac Grand Prix GTP 3.4L Engine Block Coolant Drain Plug

"Buford T. Justice" wrote

Don't bother using the Dexcool. Just use the green antifreeze. The drain plugs are on each side of the block, but have you had a look underneath this engine? Good luck trying to get at either one of them. The front one is do-able, but the rear one is not accessible.

Ian

I looked under the car but didn't see anything. I will look again.

Why use green? I heard it had chemicals that were bad for the water pump in newer cars with aluminum engines and such.

BTJustice

What do the drain plugs look like exactly? Are they screwable plugs?

BTJustice

The front one is between the oilfilter and starter morter. The back one is close to the crank sensor. Both difficult to get to if you don't have a lift. In current engines the green stuff may be more harmful than the orange stuff...

Not to ask a dumb question, but would simply opening up the front one with the car at a forward incline completely empty the engine block?

BTJustice

"Buford T. Justice" wrote

What does the car originally come with? I think that in 95 those vehicles still used the green. Aluminum compatible green a/f has been around for years. I'm not sure if you are aware of the fact that there have been aluminum components in automotive engines 'before' 1995.

Ian

Yes I am aware of it. The neglected coolant was dark brown in color. I believe it was originally red as I am pretty sure GM started using in at the

BTJustice

If it's dark brown I would recommend using a good acidic flush if you DO NOT have the plastic radiator to clean out the block. There are specific flush compunds if you have the plastic radiator. Or as us rednecks like to say; raydidiyator. Once the system is flushed clean replace the thermostat, temp sending unit, and hoses to save yourself grief down the road.

I know the 3.4L motor has a problem with the head gasket leaking antifreeze into the engine oil and siezing up one of the bearings, anyone know which antifreeze does the least amount of damage though, the green or the red?

Really won't matter. If you have anti-freeze in the crankcase washing the crank/rod bearings then the color of the anti-freeze will be the last of your worries. Do you also have oil in the radiator? And, most important, how long has it been driven this way?

it was a hypothetical question, I dont have any antifreeze in my oil, at least there better not be at 4000 miles.

They certainly weren't all Dex-Cool in '95, anyway, my '95 Sunfire wasn't and neither was my parents' '95 Grand Am. If it came with Dex-Cool from the factory, it will probably be pretty much plastered all over the coolant fill cap and coolant reservoir with references to it, like "coolant does not have to be changed for 5 years or 100,000 miles if you add only Dex-Cool coolant".

I don't think it would make any real difference - I believe it's the glycol that does the damage, and that's the same in both..

Actually I think its the silica that does the damage. It breaks down and being silica it passes through your aluminum parts eating away at them like a sand blaster.

Correct, it's the silica.

I ran some super cheap antifreeze I got from the local antifreeze merchant - but its also super effective. It was basically recycled glycol mixed with RMI-25, and I ran RMI-25 with it... worked a treat, engine was cleeeean as hell.

Not that it matters, all that coolant got poured into the paddock after my accident - pole ruptured the coolant lines n' all... :-(

Nick.

Well, in that case DEX-COOL wouldn't hurt anything, since it's silicate-free, but it obviously does..

It does in what way and how? Dexcool has never hurt any of my cars.

As in, hurt things if it gets into the oil..