I'm trying to change my coolant in a 2001 Monte and I can't find the drian plug. There also seems to be oil or an oily substance in the coolant. Can anyone help. Thanks!!

 

I moved this to a relevant area, as this isn't an off topic subject.

No drain plugs on these cars. It'd be too easy, and they'd have to charge another $1,000 for it.
I just unclamp the lower radiator hose and drain it. When you refill it, make sure you purge the air from the purge valve on top of the thermostat housing.

The oily substance, does it look white?
this isn't good.

 

it is a brownish color. I'm hoping it is just real old coolant.

 

Yeah, brownish could be old coolant, how old is it?

 

Brownish you say? Sounds to me like you have oil mixing with your oil, which would be caused by a bad head gasket most likely.

These engines (3400) are know for head gasket/ and Lower/ Upper intake gaskets leaking coolant.

The 3800 is not so much known for head gasket failure, but is known to have leaking Lower intake gaskets.

It sounds to me like you either have oil in your coolant, OR like you mentioned, the coolant is just old and gumed up. Dex-Cool is know to gum up and create a nasty brownish mud in the cooling system.

In either case, a FULL radiator/ block flush is needed. However, just be aware that you may be looking at needing new gaskets sooner than later if its oil mixing with the coolant.

I honestly don't know about the 2001 Monte, but my Mom's 2000 Bonneville (with the 3800 engine) has a radiator drain plug at the very bottom right hand corner of the radiator. Its a total pain to get to, and hard to find, but it is there. In my 2006 Monte, the radiator drain plug is at the bottom left corder, and is so easy to get to. But both cars do have one. I would start hunting around the lower right corner of the radiator in your 2001, you will more than likely have to look up in the bumper to see it.

 

I would suggest that you switch to regular coolant too.

 

I REALLY dont think we have these on our cars (drain plugs)? We might, but I looked for an hour without getting up from under my car... NO LUCK. If it is there and somone finds it, let us know.
And if it were oil leaking into the coolant, wouldnt it be whitish grey like said above??

 

Well like I said, this was my Mom's Bonneville with the 3800 that has the drain plug on the radiator (its on the right side, on the front side of the radiator, burried in the bumper, but its there)...but I would have thought all cars with the 3800 would have one then...and also like I said my Monte (all though it is newer and a 3500), also has a drain plug (my Monte has it on the left side, on the back side of the radiator, right out in the open, easy to get too).

And yes the milky white will form with oil in the coolant, but its also a milky brownish color, usually forms on the surface of things (like the fill cap)...the term "browish" is kinda vegue, so I was just thowing out ideas to look for. It would very well be the Dex-Cool turning to "brownish" colored mud (which would feel oily)...

 

I finally found the drain plug. It is on the drivers side and on the inside toward the engine. It is easier to get to if you take off the rubber splash shield. I drained the coolant and put in Prestone. You also have to open a couple of air release valves on top of the engine while you are putting the new coolant in. I should be good to go.

 

I also found the drain plug on the drivers/engine side (the very most bottom of the drivers side radiator tank). After removing the air dam on my 02 Monte last night I was able to feel it. It has atwo round tabs sticking out to make you think you can just use a flat stubby screwdriver, but those tabs just broke right off. Then I felt a hex on the outer edge of the plug and used an 11/16 deep socket to loosen the plug. I had to push up a little on the radiator to get the socket on it and didn't have to take the plug all the way out. Coolant started comming out the center of the bottom mount after one turn. So yes a plug does exist on the 2002 Monte.